The Chess Variant Pages
A. A violent order is disorder; and
B. A great disorder is an order. These
Two things are one.

-- Wallace Stevens, Connoisseur of Chaos


Too much of everything is just enough.

-- The Grateful Dead, I Need a Miracle

Jupiter

Jupiter is a truly large chess variant played on a 16 by 16 board. I, Adrian King, must take responsibility for it, although in my defense, I claim that I was incited by the the contest to design large chess variants, for which Jupiter is a non-competing submission.

The Origins of Jupiter

Jupiter is the third in a series of progressively larger games I have come up with. The first was Scirocco, a 10 x 10 chess variant, and the second was Typhoon, a 12 x 12 variant.

Any reasonable person would stop after designing a game the size of Typhoon, in which each player starts off with 46 pieces, as in Chu Shogi. I find it hard to explain why I feel it necessary to inflict an even larger game on the world, except that I can. Perhaps you will accept the excuse that when I first saw "contest to design a large chess variant", I misunderstood it as "contest to design as large a chess variant as possible".

The examples of some of the very large Shogi variants have served to egg me on in this misadventure. Tenjiku Shogi (played on a 16 x 16 board) and Dai Dai Shogi (played on a 17 x 17 board) both contain an appalling miscellany of bizarre pieces. The existence of Tai Shogi (played on a 25 x 25 board) has given me precedent for the pursuit of size for its own sake.

The name "Jupiter" results from my attempt to come up with something much bigger than a "typhoon". A typhoon is probably at the upper limit of meteorological phenomena on Earth, but the planet Jupiter has a much bigger and more violent atmosphere, and the images we see of the vast, swirling, churning Jovian atmosphere suggest something of the feeling I wanted to evoke with this immense, sprawling chess game.

The Initial Setup

Jupiter is a game on a 16 x 16 board for two players, called Blue and Tan. Blue moves first.

The setup is rather flexible. Except for the pawn row, where the setup is fixed, the setup is designed in terms of pairs of pieces. One member of each pair goes on the left side of the board, and the other on the right, but it does not matter which one goes on which side, provided that the overall setup is symmetrical.

The symmetry requirement is as follows: Tan's setup must be identical to Blue's (rotated 180 degrees about the center of the board). That is, Blue and Tan have the same pieces at a1 and p16, b1 and o16, c1 and n16, and so on. (Unlike Typhoon, Jupiter does not allow Blue's arrangement to be a mirror image of Tan's; this is because some pieces in Jupiter move in ways that do not have left-right symmetry, so that Tan could make a mirror image of Tan's setup noticeably weaker than Tan's own initial position.) By convention, the King starts just left of center on the first rank, that is, on h1 for Blue and i16 for Tan.

Tan gets to choose the entire initial setup. (This is only a modest compensation for the fact that Blue gets the first move, since no setup appears to provide much advantage for either player over any other setup.)

The initial setup looks like this for each player (either member of a pair may be placed in a spot where the name of a pair appears, except that the King and Commoner are usually placed as shown):

   Went-Between Pair    Go-Between Pair     Go-Between Pair    Went-Between Pair   
FuBerolinaBerolinaPawnPawn GuardPawnPawn PawnPawnGuard PawnPawnBerolinaBerolinaFu
Side PairBarbarian PairOdd PairSquare Pair Horse PairSkewed PairMetal PairPrincely Pair Princely PairMetal PairSkewed PairHorse Pair Square PairOdd PairBarbarian PairSide Pair
Dagger PairLinear Pair Colorbound Pair  Fifth PairAncient PairShort Pair Short PairAncient PairFifth Pair  Colorbound Pair Linear PairDagger Pair
Scattered PairRelay PairMagnetic PairTank Pair Odder PairPretentious PairChu PairPoison Pair Poison PairChu PairPretentious PairOdder Pair Tank PairMagnetic PairRelay PairScattered Pair
Artillery PairLetter Pair Skipping Pair  Dragonlet PairDirectional PairMover Pair Mover PairDirectional PairDragonlet Pair  Skipping Pair Letter PairArtillery Pair
Lance PairHook PairFat PairAnimal Pair Queenlet PairBent PairGuardian PairRegal Pair (King) Regal Pair (Commoner)Guardian PairBent Pair Queenlet Pair Animal PairFat PairHook PairLance Pair

The Pieces

Here is a summary of the pieces used in the game. Their moves are described in a notation that I hope will not be too obscure (at least to those familiar with other chess variants), but if it is not clear, each piece is described in detail below.

All of the pieces from Typhoon also appear in Jupiter, with the same promotions. Furthermore, the Frog and Emperor, which appear in Scirocco but not Typhoon, are both present in Jupiter (although the Emperor has been renamed the Ancient Emperor).

PieceAbbreviationAbilities Promotes toPromoted AbbreviationPromoted Abilities
Lance Pair: a1, p1, a16, p16
Fire Horse FHforward R + back N Flying Ox FOB + forward R + back R
Ghost Warrior GWforward R + back F Free Boar FBB + side R
Hook Pair: b1, o1, b16, o16
Hooklet HooR2; then optionally R2 again at right angles; must stop if it makes a capture Boyscout Boyalternates F moves in two directions at right angles to each other; must stop if it makes a capture
Hawklet HawF + W; then optionally F + W again in any direction except back to starting square Girlscout Giralternates W moves in two directions at right angles to each other; must stop if it makes a capture
Fat Pair: c1, n1, c16, n16
Marquis MaW + N Abbot AbN + B4
Priest PrF + N Duke DuN + R4
Animal Pair: d1, m1, d16, m16
Stork StW (capturing) + A Queen QR + B
Goat GoF (moving) + D Lioness LiW + F + D + N + A
Queenlet Pair: e1, l1, e16, l16
Cicada Cilike Q3, but must hop at least one piece (of either color; not captured) along the way Typhoon TyF + A + R3; need not stop when it makes a capture orthogonally, and so may capture up to 3 pieces in a turn
Salamander SaQ3 (moving); W + F (capturing) Genie GeQ3 + capture by igui on adjacent squares
Bent Pair: f1, k1, f16, k16
Toucan TouW + F; also, may capture as W, then make a 2nd W step at right angles, where destination space may also contain an opposing piece, in which case 2 pieces are captured Capricorn CapB; then optionally, if destination space was empty, a 2nd B move at right angles
Crow CroF + D; also, may capture as F, then make a 2nd F step at right angles, where destination space may also contain an opposing piece, in which case 2 pieces are captured Great Hook GrHR; then optionally, if destination space was empty, an R3 move at right angles
Guardian Pair: g1, j1, g16, j16
Gold General GGW + forward F Horned Owl HOB4 + side D + back D + forward Parrot
Ferocious Leopard FLF + forward W + back W Diving Osprey DOR4 + back A + forward Raven
Regal Pair: h1, i1, h16, i16
King KW + F; royal Emperor EmQ2 + N; royal
Emperor of Emperors EEW + F + D + N + A + (3,0) leaper + C + Z + (3,3) leaper; also, capture by igui (shooting) along Q lines; royal
Commoner CoW + F Wildebeest WiN + C
Artillery Pair: a2, p2, a15, p15
Blunderbuss BlnR4 (moving); captures like R4, but must hop exactly one piece (of either color; not captured) along the way Cardinal CarN + B
Crossbow CboB4 (capturing); moves without capturing like B4, but must hop exactly one piece (of either color; not captured) along the way Marshall MarN + R
Letter Pair: b2, o2, b15, o15
Eye Eyebent rider that moves consecutively as forward or back W, then another step in the same direction, then side W; may stop anywhere along the line of movement, and must stop if it makes a capture Far Queen FaQQ, but not to any of the 2 nearest spaces along any line of movement; blockable on either of those 2 spaces
Yew Yewbent rider that moves consecutively as side W, then forward R3; may stop anywhere along the line of movement, and must stop if it makes a capture Talia TalB, but not to diagonally adjacent space (blockable there)
Skipping Pair: d2, m2, d15, m15
Thisaway ThiA + forward W + back W + side D + sidemost N West Wind WWiforward R3 + back R3 + right R + right B + left N
Thataway ThaA + side W + forward D + back D + forwardmost N + backmost N East Wind EWiforward R3 + back R3 + left R + left B + right W + right C
Dragonlet Pair: f2, k2, f15, k15
Dragon Pony DrPW + B3 Withdrawer WdrQ (moving); captures by moving like Q any distance in opposite direction from adjacent opposing piece, which is captured
Dragon Duke DrDF + R3 Coordinator CooQ (moving); captures upon completion of move any opposing piece on same rank as Coordinator and on same file as any friendly royal piece, or on same file as Coordinator and on same rank as any friendly royal piece (can capture up to 2ce the number of friendly royal pieces in one turn)
Directional Pair: g2, j2, g15, j15
Right General RtGF + forward W + back W + left W Whale Whlforward R + back R + back B
Left General LfGF + forward W + back W + right R White Horse WhHforward R + back R + forward B
Mover Pair: h2, i2, h15, i15
Vertical Mover VtMside W + forward R + back R Tiger Horse TiHF + D + N + A + C; also, may capture as N, then move or capture as W (so may capture 2 pieces on a turn)
Side Mover SdMforward W + back W + side R Zoom ZooQ (moving); relays to any friendly piece along unobstructed Q lines the ability to move (but not capture) as Q
Scattered Pair: a3, p3, a14, p14
Blue Gecko BlGforward W + forward right B4 + back right F + back R2 + left R2 + forward left F Boxer BoxW + F + (0,3) leaper + C + Z + (3,3) leaper
White Fox WhFforward R2 + right W + back right B4 + back left F + left R2 + forward left F Foursquare FsqF + N + C + Z + (3,3) leaper
Relay Pair: b3, o3, b14, o14
Relay Wazir RlWW (moving and capturing); also, relays to any orthgonally or diagonally adjacent piece the ability to move or capture as W Soaring Eagle SEgR + back B + forward Raven
Relay Firzan RlFF (moving and capturing); also, relays to any orthgonally or diagonally adjacent piece the ability to move or capture as F Horned Falcon HFlB + back R + side R + forward Parrot
Magnetic Pair: c3, n3, c14, n14
Come Here CmHW + F (moving); cannot capture, but may pull any opposing piece that is 2, 3, or 4 steps away along unobstructed Q line one step closer along that line Hippogriff HgrN + Grasshopper, where Grasshopper moves along Q lines, hopping one piece of either player (not captured) to space immediately beyond hopped piece, where Grasshopper may capture if destination space contains opposing piece
Go Away GoAW + F (moving); cannot capture, but may push any opposing piece that is 1, 2, or 3 steps away along unobstructed Q line one step farther along that line (if destination space is empty); may not push piece off board Werewolf WwfW + F + Nightriderhopper, where Nightriderhopper moves along Nightrider lines, hopping one piece of either player (not captured) to space one N-step beyond hopped piece, where Nightriderhopper may capture if destination space contains opposing piece
Tank Pair: d3, m3, d14, m14
Ox Tank OxTW; also, may move as W to a space occupied by a friendly piece, which is pushed one more step in the same direction. The pushed piece may capture if an opposing piece lies on its destination square, or may in turn push yet another friendly piece, which may also capture if an opposing piece lies immediately beyond it. However, no more than 2 friendly pieces may be pushed by the Ox Tank. It is legal for the Ox Tank to push a friendly piece off the board Bishop General BGnB; also, when capturing (along B lines), may hop over any number of pieces (friendly or opposing) to land on an opposing piece any distance beyond last piece hopped. However, when hopping, may neither hop over nor capture a royal piece, a Rook General, or another Bishop General (friendly or opposing)
Dragon Tank DrTF; also, may move as F to a space occupied by a friendly piece, which is pushed one more step in the same direction. The pushed piece may capture if an opposing piece lies on its destination square, or may in turn push yet another friendly piece, which may also capture if an opposing piece lies immediately beyond it. However, no more than 2 friendly pieces may be pushed by the Dragon Tank. It is legal for the Dragon Tank to push a friendly piece off the board Rook General RGnR; also, when capturing (along R lines), may hop over any number of pieces (friendly or opposing) to land on an opposing piece any distance beyond last piece hopped. However, when hopping, may neither hop over nor capture a royal piece, a Bishop General, or another Rook General (friendly or opposing)
Odder Pair: e3, l3, e14, l14
Neartaker NrtW + F (moving); captures by approach (if an opposing piece is adjacent to the Neartaker's arrival square and along its line of movement, that piece is captured) Teleporter TlpQ (moving); also, relays to any friendly piece less than 2 steps away (regardless of intervening pieces, if any) the ability to move (without capturing) to the square at the same distance and direction from any friendly royal piece; also relays to any friendly piece less than 2 steps away from any friendly royal piece the ability to move (without capturing) to the square at the same distance and direction from Teleporter
Intertaker IntW + F (moving); custodian capture (on completion of move, any opposing piece orthogonally or diagonally adjacent to arrival square is captured if a piece of the Intertaker's own side is immediately beyond it in the same direction from Intertaker's arrival square, such that the captured piece is sandwiched between the Intertaker and a piece friendly to the Intertaker; can capture up to 7 pieces on a turn) Halmopper HlmW + F; also, may make any number of consecutive Grasshopper moves (but must stop if it makes a capture), where Grasshopper moves along Q lines, hopping one piece of either player (not captured) to space immediately beyond hopped piece, where Grasshopper may capture if destination space contains opposing piece
Pretentious Pair: f3, k3, f14, k14
Flying Dragon FlDB2 Doubler DblQ (moving); any piece (friendly or opposing) along an unobstructed Q line from Doubler may make 1 or 2 consecutive moves on the same turn (and need not stop if captures on 1st move). Doubled piece unaffected by immobilization/doubling/burning/poison at end of 1st move if it makes 2nd move
Violent Ox VOxR2 Poisoner PsnQ (moving); any piece (friendly or opposing) along an unobstructed Q line from Poisoner is poisoned (if capturer of poisoned piece ends turn on same space where poisoned piece was captured, the capturer is also captured)
Chu Pair: g3, j3, g14, j14
Kylin KylF + D King Lion KLiW + F + D + N + A; also, may capture as W + F, then make a 2nd move as W + F, possibly changing direction (including back to starting square) and possibly capturing a 2nd piece; also, may pass a turn
Phoenix PhxW + A Queen Cannon QCnQ (moving and capturing); also, may capture along Q lines by hopping one piece (of either player; not captured) to land any distance beyond the hopped piece on an opposing piece, which is captured
Poison Pair: h3, i3, h14, i14
Kamikaze KamQ2; if Kamikaze captures an opposing piece, the Kamikaze is captured too Ancient Emperor AEmW + D + A; royal
Deadly Nightshade DNiW + F; poison (if capturer of Deadly Nightshade ends turn on same space where Deadly Nightshade was captured, the capturer is also captured) Frog FrgW + F + (3,0) leaper + (3,3) leaper
Dagger Pair: a4, p4, a13, p13
Cuckoo Cuside W + back W + forward D; also, on forward-W, side-W, or back-D space, may convert an opposing piece to a friendly piece (this takes a turn) Longleaper LoQ (moving); to capture, hops along Q lines to empty space beyond opposing piece (immediately beyond or through any number of clear spaces beyond); opposing piece is captured; may capture again repeatedly on same turn in the same direction as long as a capture is available in that direction (but may stop while a capture is still available)
Hummingbird Huside W + back W + forward D; also, may interchange its position with any piece (friendly or opposing) on a W, forward-D, or back-D space Immobilizer ImQ (moving); paralyzes all adjacent opposing pieces; a paralyzed piece may capture itself (this takes a turn)
Linear Pair: b4, o4, b13, o13
Rankrider Rrdside R Fiery Dragon FiDB; captures not only opposing piece it lands on but all opposing pieces orthgonally or diagonally adjacent to arrival square as well. If an opposing piece ends its turn on a space adjacent to Fiery Dragon, opposing piece is captured. If Fiery Dragon lands next to an opposing Fiery Dragon, both are captured (possibly along with other opposing pieces)
Filerider Frdforward R + back R Water Buffalo WBfB + forward R2 + back R2 + side R
Colorbound Pair: d4, m4, d13, m13
Camel CC Squirrel SqD + N + A
Bishop's Dog BDB3 Centaur CeW + F + N
Fifth Pair: f4, k4, f13, k13
Right Knight RtNforwardmost right N + rightmost back N + backmost left N + leftmost forward N Golden Bird GBdB3 + side R2 + forward R + back R
Left Knight LfNforwardmost left N + rightmost forward N + backmost right N + leftmost back N Great Dragon GDrB3 + side R + forward R2 + back R2
Ancient Pair: g4, j4, g13, j13
Alfil AA Scirocco ScW + B
Dabbaba DD Dragon Kite DKF + R
Short Pair: h4, i4, h13, i13
Wazir WW Zag ZaF + A + hop-capture over orthogonally adjacent pieces
Firzan FF Zig ZiW + D + hop-capture over diagonally adjacent pieces
Side Pair: a5, p5, a12, p12
Otter OtF + side R4 + forward W Missionary MiW + B2 (moving); cannot capture, but may convert opposing piece to friendly piece when the opposing piece is adjacent to arrival square of Missionary and on Missionary's line of movement
Beaver Beside R4 + back R + forward F + forward W Sorcerer SoW + B2 (moving); may capture one or more opposing pieces when first piece captured is adjacent to arrival square of Sorcerer and on Sorcerer's line of movement; additional pieces are captured along the same line as far as that line is occupied by opposing pieces, so Sorcerer can capture up to 14 pieces at a time on 16 x 16 board. Always captures all possible pieces if captures any piece; cannot capture just part of a line of opposing pieces
Barbarian Pair: b5, o5, b12, o12
Eastern Barbarian EBaforward R2 + back R2 + forward F + side W Communist CstW + B2; also, upon completion of move, captures all adjacent promoted pieces (friendly or opposing)
Western Barbarian WBaside R2 + forward W + back W + forward F Royalist RoyF + R2; also, may leap from anywhere on board to any space adjacent to a friendly royal piece (whether target space is occupied or not, even by a friendly piece)
Odd Pair: c5, n5, c12, n12
Overtaker OvF + W (moving); hop-capture over adjacent piece Nightrider NrNr (a series of N steps along a straight line, in the same way as a Rook is a series of W steps along a straight line)
Undertaker UnF + W (moving); captures by withdrawal (moving one step directly away from adjacent opposing piece, which is captured) Dayrider DaF + W (moving); Dabbaba-rider + Alfil-rider (can repeat Dabbaba or Alfil move along a straight line, in the same way as a Rook is a series of W steps along a straight line)
Square Pair: d5, m5, d12, m12
Chariot ChR4 Octopus OcF then R outwards; can move but not capture as F
Wagon WaR, but not to orthogonally adjacent space (blockable there) Spider SpW then B outwards; can move but not capture as W
Horse Pair: e5, l5, e12, l12
Knight NN Rook RR
Dervish DeD + A; also, adjacent friendly pieces can hop over Dervish (without capturing it) Harpy HaQ (moving); cannot capture; relays to friendly pieces ability to move as N on squares one N-move away
Skewed Pair: f5, k5, f12, k12
Twist TwiW + right forward F + rightmost forward N + left back F + leftmost back N Mad Hatter MdHQ (moving) + N (capturing)
Tango TgoW + forwardmost left N + left forward F + right back F + backmost right N March Hare MrHN (moving) + Q (capturing)
Metal Pair: g5, j5, g12, j12
Silver General SGF + forward W Vulture VuB (moving) + R (capturing) + W + F
Copper General CGforward F + forward W + back W Ibis IbR (moving) + B (capturing) + W + F
Princely Pair: h5, i5, h12, i12
Drunk Elephant DEF + forward W + side W Elephant Prince EPF + W (moving); N + A (capturing); royal
Blind Tiger BTF + side W + back W Tiger Prince TPF + W (moving); D + N (capturing); royal
Two Fus: a6, p6, a11, p11
Fu Fuforward W Zebra ZZ
Four Berolinas: b6 - c6, n6 - o6, b11 - c11, n11 - o11
Berolina Berforward F (moving) + forward W (capturing) Mock Turtle MkTA (moving) + R4 (capturing)
Eight Pawns: d6 - e6, g6 - j6, l6 - m6, d11 - e11, g11 - j11, l11 - m11
Pawn Pforward W (moving) + forward F (capturing) Tadpole TaF + (3,0) leaper (moving and capturing); W (capturing)
Two Guards: f6, k6, f11, k11
Guard GuW (moving) + F (capturing) Bishop BB
Went-Between Pair: c7, n7, c10, n10
Go-Between GBtforward W + back W Tribble TrbD; also, may reproduce by creating a new Tribble on an empty square one D-move away
Go-Along GAlside W Sultan SulF + C; royal
Go-Between Pair: f7, k7, f10, k10
Lantern Laforward F Parrot PaW + D + igui capture on orthogonally adjacent spaces; also, hop-capture on orthogonally adjacent spaces, where destination space may also contain an opposing piece, in which case 2 pieces are captured; also, may pass a turn
Banner Baforward W + side W Raven RaF + A + igui capture on diagonally adjacent spaces; also, hop-capture on diagonally adjacent spaces, where destination space may also contain an opposing piece, in which case 2 pieces are captured; also, may pass a turn

As in Scirocco and Typhoon, most of the initial pieces are fairly weak, none being worth more than about a Rook. This leads to a relatively quiet opening. However, many of the promoted pieces are both strong and strange, so endgames should be wild and extremely varied, depending on what pieces manage to promote.

The King has a special promotion rule, as explained below.

In alphabetical order:

Abbot (Ab)

The Abbot moves and captures like a Knight, or like a Bishop, but not farther away than four spaces.

The Abbot is based on the frequently invented combination of Knight and Bishop. Since Grand Chess was a part of the inspiration for this game, I thought I should have a Knight + Bishop piece in the game somewhere, but I seemed to have too many strong promoted pieces, so I limited the range of the Bishop movement. The Knight + Bishop combination is called the "Cardinal" in Grand Chess, and I thought I'd keep the ecclesiastical theme in the Abbot's name (as well as the Priest's).

Alfil (A)

The Alfil is a (2,2) leaper; that is, it leaps two spaces diagonally, ignoring any intervening piece.

The Alfil is a piece of ancient lineage, being the predecessor to the modern Bishop. It is a very weak piece, worth not much more than a Pawn, although it promotes fairly strongly (to the Scirocco, which is the piece I used in the game of Scirocco to replace the modern Bishop, which replaced the Alfil -- so there is a logic behind this promotion).

Banner (Ba)

The Banner moves and captures as a Wazir in the forward and side directions; it cannot move backwards.

The Banner, along with its twin the Lantern, replaces the Go-Betweens of Chu Shogi. The Go-Betweens move only straight forward and backward, but I thought that being confined to a single file was too limiting a life, so I gave the Banner a little more freedom.

Beaver (Be)

The Beaver moves and captures as a Firzan in the two forward directions, or one step forward as a Wazir, or up to four steps to the left or right as a Rook, or straight backwards any distance as a Rook.

The Beaver and its twin the Otter are kin to the Chu Shogi Side Mover; they are difficult to advance, but their strong sideways movement makes them quite useful as defenders.

Bishop (B)

The Bishop moves the same as its Orthochess equivalent; that is, it moves when not capturing diagonally any number of clear spaces, and captures by moving diagonally across any number of clear spaces to the first space occupied by an opposing piece, which the Bishop replaces.

Bishop's Dog (BD)

The Bishop's Dog moves and captures like a Bishop, but not farther than three spaces from its starting square.

The name is taken from the Bishop and from the Lion Dog, a piece from some of the larger Shogi variants that moves like a Queen up to three spaces.

Blind Tiger (BT)

The Blind Tiger moves and captures like a Commoner, but not straight forwards.

The Blind Tiger is retained from class=extern Chu Shogi. In that game, the Blind Tiger does not promote to a royal piece, as it does in Typhoon; however, the idea of twinning the Drunk Elephant and Blind Tiger (and making their promotions similar, too) seemed to good to pass up.

Boyscout (Boy)

The Boyscout traces a zigzag path. It moves and captures by moving alternately one step in one diagonal direction and one step in another direction at right angles. It must stop if blocked by a friendly piece or if it makes a capture by landing on an opposing piece.

A Boyscout at c4 can move along these lines:

The Boyscout is one of the gems in Anthony Dickins's A Guide to Fairy Chess; Dickins reports that the piece was invented by J. de A. Almay of Budapest.

Camel (C)

The Camel is a (3,1) leaper; that is to say, it leaps directly to any space that could be reached by moving three spaces along any rank or file, and then one space at right angles. It is thus a sort of extended, colorbound Knight.

As is typical of the initial Typhoon pieces, the Camel is fairly weak, but not worthless (it's worth a little less than a Knight). The Camel's movement geometry is also different from that of every other unpromoted piece, so that it can attack without being attacked.

Capricorn (Cap)

The Capricorn moves and captures by first moving like a Bishop; then, if the arrival square is empty, it may turn 90 degrees to the right or left and again move like a Bishop. A Capricorn cannot capture more than one piece on a turn, and must stop when it makes a capture.

In the middle of an empty board, a Capricorn can half the squares on the board.

The Capricorn is taken from class=extern Tai Shogi.

Centaur (Ce)

The Centaur moves and captures as a Wazir, Firzan, or Knight.

The Centaur's name is taken from its ability to move as a man (Commoner; German Mann) or horse (Knight).

Chariot (Ch)

The Chariot moves and captures like a Rook, but not farther away than four spaces.

The Chariot is one of the two Rook-like pieces I derived by reducing the strength of a Rook, the other being its twin, the Wagon.

Ralph Betza has conducted some experiments with this piece.

Cicada (Ci)

The Cicada moves and captures along Queen lines up to three spaces away. However, it must hop over at least one piece on the way to its destination square (it may hop over two). The piece or pieces hopped over are not captured. For example, given a Blue Cicada at b2, a Tan Bishop at b3, a Blue Guard at d4, a Blue Knight at c2, a Tan Rook at d2, and a Tan Spider at e2, the Cicada may make any of the following moves:

The Cicada is fairly agile in the earlier parts of the game when there are plenty of pieces to hop over, but should be exchanged off or promoted before the board becomes too sparsely populated.

The Cicada is named for the insect whose loud droning song is characteristic of summer in many parts of the world; cicadas are particularly common in Japan, so many historical games of Chu Shogi must have been played to its accompaniment.

Commoner (Co)

The Commoner (known in some games as the "Mann") moves and captures exactly like a King, but is not royal (capturing it does not end the game).

This piece was handed down from Courier Chess, where it also sits next to the King in the initial setup.

Copper General (CG)

The Copper General moves and captures like a Commoner, but not orthogonally sideways or diagonally backwards; in the middle of an empty board, it can move to any of four squares.

The Copper General is a piece from Chu Shogi. It is part of a logical progression: a Gold General that can reach six squares, a Silver General that can reach five, and the Copper General, which can reach four. The pieces are set up in that order on the first rank of a Chu Shogi board.

Crow (Cro)

The Crow has a complex move. It can do any of the following:

The Crow is a variation on the Raven; whereas the Raven's second step is either 0 or 180 degrees from the direction of its first step, the Crow's second step makes an angle of 90 degrees to its first.

Cuckoo (Cu)

The Cuckoo moves and captures like a Wazir sideways and backwards, or like a Dabbaba forwards. In addition, on the orthogonally adjacent squares to the left, right, and straight ahead, or on the square two steps straight back (ignoring any piece on the square one step straight back), the Cuckoo may, without moving, convert an opposing piece to a friendly piece; this takes a turn.

For example, given a Blue Cuckoo on a4 and a Tan Pawn on a5, the Cuckoo may transform the Tan Pawn into a Blue Pawn. This makes the Pawn effectively change direction; that is, the transformed Blue Pawn moves northwards like all other Blue Pawns, and does not somehow remember its previous southward orientation from its life as a Tan Pawn.

Because the Cuckoo is not particularly agile, its ability to change the ownership of a piece is not as formidable as you might suppose. However, the ability makes it more awkward to exchange an orthogonally moving piece for a Cuckoo.

Dabbaba (D)

The Dabbaba is a (2,0) leaper; that is, it leaps two spaces orthogonally, ignoring any intervening piece.

The name "Dabbaba" was used for various unorthodox pieces in medieval Islamic chess variants. The move we generally associate with this name today is the one from Timur's Great Chess. The word "dabbaba" means a kind of war machine; its English translation is "sow", but I have no idea what it looks like.

Dayrider (Da)

The Dayrider may move and capture as a Dabbaba or Alfil; it may also repeat a Dabbaba's or Alfil's move as far as it wishes in the same direction through clear spaces until it reaches the edge of the board, or is blocked by a friendly piece, or lands on an opposing piece, capturing it. In addition, the Dayrider may move without capturing as a Commoner (to prevent the Dayrider from being colorbound).

In short, the Dayrider is a Dabbabarider plus an Alfilrider plus a noncapturing Commoner.

I invented the Dayrider as a complement to its twin, the Nightrider.

Dervish (De)

The Dervish moves and captures two steps orthogonally or diagonally. It leaps any intervening piece without capturing or being blocked by it. In addition, any friendly piece on any of the eight adjacent squares may leap to the opposite side of the Dervish (to move or capture, provided the target square is not occupied by a friendly piece). Thus, if there is a Blue Dervish on b5 and a Blue Pawn on a4, the Pawn may leap to c6 (or make a normal Pawn move to a5).

A piece cannot promote on a turn when it uses the Dabbaba- or Alfil-like move relayed by a Dervish; it can promote only when moving under its own power.

A dervish is a Muslim ascetic. Dervish orders are known for their whirling dances (to induce a trance-like state). The movements of the adjacent pieces across the Dervish reminded me of whirling, whence the name.

Diving Osprey (DO)

The Diving Osprey can move and capture like a Rook up to 4 steps, or like an Alfil in the backward directions. It can also move like a Raven in the forward directions only; that is, it can:

The Diving Osprey was inspired by the Chu Shogi piece called the Soaring Eagle, but is less powerful.

Dragon Kite (DK)

The Dragon Kite moves and captures one step diagonally or any number of steps orthogonally, that is, as a Firzan or Rook. This is the same as the move of the promoted Rook (or Dragon King) in Shogi; the Dragon King also exists as an unpromoted piece in Chu Shogi.

I renamed this piece "Dragon Kite" from "Dragon King" to preserve the wind-related theme of its twin, the Scirocco (which was itself renamed from "Dragon Horse").

Drunk Elephant (DE)

The Drunk Elephant moves and captures like a Commoner, but not straight backwards.

The Drunk Elephant is retained from Chu Shogi. As in that game, it promotes in Typhoon to a royal piece (although not to the Crown Prince of Chu Shogi, which moves just like a King).

In Chu Shogi, the Drunk Elephant starts on the first rank, and is such a good defender of the King that it almost never ventures far enough forward to promote. The Drunk Elephant in Typhoon starts on the third rank, somewhat increasing its chance of actually promoting to an Elephant Prince.

The abbreviations for the Drunk Elephant and the Dervish differ only in case; if there is a chance of ambiguity, you might prefer the abbreviations "DEl" and "Der".

Duke (Du)

The Duke moves and captures like a Knight, or like a Rook, but not farther away than four spaces.

The Duke is to the Marquis as the Abbot is to the Priest; it extends the one-step move to a four-step ride. However, I made the Marquis promote to the Abbot, not to the Duke, so that the promoted Marquis wouldn't be a superset of the Marquis (meaning there might be situations where you would decline promotion). Hence the Priest promotes to the Duke, not to the Abbot.

The Knight + Rook combination is called the "Marshall" in Grand Chess, and I thought I'd give this piece a vaguely military sounding name. "General" sounded too much like "Genie", and is also the translation of "Firzan". The two-character abbreviation for "Colonel" would have been identical to that of "Commoner". I settled on "Duke"; the name is hard to confuse with that of other pieces, and was originally a military title, from Latin dux, meaning "leader".

Elephant Prince (EP)

The Elephant Prince, a royal piece, moves when not capturing as a Commoner, and captures like Knight or Alfil.

The Elephant Prince can capture on more spaces than a King, and so is better than a King as an offensive piece; however, a King can single-handedly checkmate an Elephant Prince.

Emperor (Em)

The Emperor, a royal piece, moves and captures like a Knight, or like a Queen up to two steps; it is thus nearly as powerful as a Lioness. The strength of this promotion may give your King a powerful incentive to make the risky journey to the promotion zone.

The Emperor is only one of two possible promotions of the King; the other is the Emperor of Emperors. The entry for the King describes the difference.

Emperor Of Emperors (EE)

The Emperor of Emperors is a royal piece. It leaps to move or capture to any square within three steps of its starting square; that is, it moves as a non-capturing Wazir, Firzan, Dabbaba, Knight, Alfil, (3,0) leaper, Camel, Zebra, or (3,3) leaper. The Emperor of Emperors may also capture any piece a Queen could capture, but the Emperor of Emperors does so without moving; various authors have called this kind of capture "rifle capture", "shooting", or "igui". The game of Rifle Chess is based on rifle capture.

Players of Rifle Chess sometimes use the rule that capture is obligatory, but the Emperor of Emperors is never obliged to make a capture.

The Emperor of Emperors is an exceedingly powerful piece, but difficult to obtain. The Emperor of Emperors is only one of two possible promotions of the King; the other is the Emperor. The entry for the King describes the difference, and tells why it is easier to get an Emperor than an Emperor of Emperors.

Ferocious Leopard (FL)

The Ferocious Leopard moves and captures like a Commoner, but not sideways orthogonally; in the middle of an empty board, it can move to any of six squares.

The Ferocious Leopard is a piece from Chu Shogi. It is certainly a useful piece in both defense and offense, but the inventor may have overstated the case in calling it "ferocious".

Fire Horse (FH)

The Fire Horse moves and captures forwards like a Rook, or backwards like a Knight.

Starting in a back corner of the board, the Fire Horse is difficult to get moving in any direction except straight ahead. Its inspiration was the Chu Shogi Lance, which starts in the same position, and also moves forwards like a Rook (but the Lance can't move backwards).

Firzan (F)

The Firzan, also known variously as "Fers", "Ferz", or "Farzin", moves and captures one step diagonally.

The Firzan (Arabic, from the Persian word for "general") was present in the oldest forms of chess of which we are aware, but has been replaced in Orthochess by the Queen.

Flying Ox (FO)

The Flying Ox moves and captures like a Queen, except that it may not move or capture sideways like a Rook.

The Flying Ox is a Chu Shogi piece, although in Chu Shogi it promotes from a different piece (the Vertical Mover, which doesn't appear in Typhoon).

Free Boar (FB)

The Free Boar moves and captures like a Queen, except that it may not move or capture forwards or backwards like a Rook.

The Free Boar is a Chu Shogi piece, although in Chu Shogi it promotes from a different piece (the Side Mover, which doesn't appear in Typhoon).

Fu (Fu)

The Fu moves and captures one step straight ahead.

The Fu is the pawn used in Shogi and Chu Shogi, and "Fu" is the usual Japanese term for the piece (the characters written on the piece actually read "fuhyou" or "hohei", meaning "foot soldier").

Genie (Ge)

The Genie moves and captures as a Queen, but not farther away than three spaces. In addition, the Genie can capture an opposing piece on an (orthogonally or diagonally) adjacent square without moving.

The Genie is a reasonably powerful piece in the endgame because of its ability to capture a protected piece without exposing itself to harm. However, it is generally not the most powerful piece in the game, as it is in Scirocco; it is relatively weaker on the 16 x 16 board compared with long-range pieces like the Queen, and there are a number of other powerful promoted pieces available.

Ghost Warrior (GW)

The Ghost Warrior moves and captures forwards like a Rook, or backwards like a Firzan.

Starting in a back corner of the board, the Ghost Warrior is difficult to get moving in any direction except straight ahead. Its inspiration was the Chu Shogi Lance, which starts in the same position, and also moves forwards like a Rook (but the Lance can't move backwards).

Girlscout (Gir)

The Girlscout traces a zigzag path. It moves and captures by moving alternately one step in one orthogonal direction and one step in another direction at right angles. It must stop if blocked by a friendly piece or if it makes a capture by landing on an opposing piece.

A Girlscout at c4 can move along these lines:

The Girlscout is the orthogonal counterpart of its diagonal twin, the Boyscout.

Goat (Go)

The Goat moves and captures by leaping two steps orthogonally (like a Dabbaba); it may also move one square diagonally, but not to capture. When moving two steps, it leaps any intervening piece without capturing or being blocked by it.

The Goat is a weakened form of Kirin, a piece from Chu Shogi. The Kirin can capture as well as move one step diagonally. I wanted to add the Kirin for a bit of Chu Shogi flavor, but I already had too many eightfold leapers, so I toned it down a bit and gave it a less exotic name.

Gold General (GG)

The Gold General moves and captures like a Commoner, but not diagonally backwards; in the middle of an empty board, it can move to any of six squares.

The Gold General is a piece from Shogi (as well as Chu Shogi). It appears to have replaced the less powerful Firzan back in the prehistory of Shogi.

Great Hook (GrH)

The Great Hook moves and captures by first moving like a Rook; then, if the arrival square is empty, it may turn 90 degrees to the right or left and again move up to three squares like a Rook. A Great Hook cannot capture more than one piece on a turn, and must stop when it makes a capture.

The Great Hook is a weakened form (though still powerful enough) of the Hook Mover, a piece found in the largest Shogi variants.

Guard (Gu)

The Guard moves without capturing one step orthogonally, or captures one step diagonally. It is a sort of omnidirectional Pawn.

The Guard's Pawn-like nature allows it to participate in a Pawn chain, but unlike an easily blocked Pawn, it can get up and leave if it becomes bored.

Harpy (Ha)

The Harpy moves like a Queen, but cannot capture by itself. However, any friendly piece a Knight's move away from the Harpy is temporarily granted the additional power to move and capture like a Knight (as long as it starts its move a Knight's move away from the Harpy); pieces that can already move like a Knight are not affected. A piece cannot promote on a turn when it uses the Knight's move relayed by a Harpy; it can promote only when moving under its own power.

The Harpy is kin to the Knight in Knight-Relay Chess, but unlike the Relay Knight, a Harpy is not immune from capture.

The Harpy is pretty useless if you don't have a lot of pieces left; in such a case, it may be better to leave your Dervish unpromoted. If you have a bunch of weak pieces and can place the Harpy where it influences several of them, however, the Harpy can be quite powerful.

Hawklet (Haw)

The Hawklet moves and captures by moving one step, like a Commoner; then, if the arrival square is empty, it may turn in any direction except back to its starting square, and again move one step, like a Commoner. A Hawklet cannot capture more than one piece on a turn, and must stop when it makes a capture.

In the middle of an empty board, a Hawklet can reach the same squares as a Lioness; however, pieces on some squares can block the Hawklet's access to other squares, which cannot happen with the Lioness. The Hawklet's twin, the Hooklet, can also reach the same squares as a Lioness on an empty board, and is also blockable by other pieces; however, the other pieces may cut off access to different squares for the Hawklet and the Hooklet.

The Hawklet is derived from the so-called "area move" capability of a Tenjiku Shogi piece called the Lion Hawk, which can move as a Hawklet or as a Bishop.

Hooklet (Hoo)

The Hooklet moves and captures by moving one or two steps orthogonally, like a Rook; then, if the arrival square is empty, it may turn 90 degrees to the right or left and again move one or two steps orthogonally, like a Rook. A Hooklet cannot capture more than one piece on a turn, and must stop when it makes a capture.

In the middle of an empty board, a Hooklet can reach the same squares as a Lioness; however, pieces on some squares can block the Hooklet's access to other squares, which cannot happen with the Lioness. The Hooklet's twin, the Hawklet, can also reach the same squares as a Lioness on an empty board, and is also blockable by other pieces; however, the other pieces may cut off access to different squares for the Hooklet and the Hawklet.

The Hooklet is a miniaturization of a piece from the largest Shogi variants called the Hook Mover. The Hook Mover does not have the two-step restriction of the Hooklet, and so can reach any square on an empty board. The Great Hook is another (and larger) subset of the Hook Mover.

Horned Owl (HO)

The Horned Owl can move and capture like a Bishop up to 4 steps, or like a Dabbaba in the side and backward directions. It can also move like a Parrot in the forward direction only; that is, it can:

The Horned Owl was inspired by the Chu Shogi piece called the Horned Falcon, but is less powerful.

Hummingbird (Hu)

The Hummingbird moves and captures like a Wazir sideways and backwards, or like a Dabbaba forwards. In addition, the Hummingbird may exchange places with any piece (friendly or opposing) on the four orthogonally adjacent squares and on the two squares that are two steps straight ahead and straight back (ignoring any piece on the square one step straight ahead or straight back); this takes a turn.

For example, given a Blue Hummingbird on a4, a Tan Pawn on a5, a Blue Otter on a2, and a Tan Squirrel on b4, the Hummingbird may move to a5 while moving the Pawn to a4, or it may capture the Squirrel by moving to b4, or it may exchange places with the Squirrel or the Otter. The Hummingbird may also leap to the empty square at a3 or a6.

In practice, the Hummingbird's ability to exchange places with a piece is usually easier to exercise on a friendly piece than on an opposing piece.

Ibis (Ib)

The Ibis captures like a Bishop and moves without capturing like a Rook. It may also capture like a Wazir and move without capturing like a Firzan, so that it can both move and capture on adjacent squares.

Immobilizer (Im)

The Immobilizer moves like a Queen, but cannot capture. However, any opposing piece orthogonally or diagonally adjacent to an Immobilizer is incapable of movement as long as it remains next to the Immobilizer, except that the immobilized piece may capture itself ("commit suicide").

An immobilized piece cannot make any type of move under its own power except self-capture; for example, an immobilized Cuckoo cannot convert an opposing piece, an immobilized Harpy cannot relay the ability to move as a Knight, and an immobilized Raven cannot pass a turn. However, a piece with relay power (such as a Dervish or Harpy) or the ability to exchange places with another piece (a Hummingbird) can allow an immobilized piece to make a move with the relayed ability (as long as the relaying piece is not itself immobilized).

An immobilized Immobilizer cannot move, but is still capable of immobilizing adjacent opposing pieces. This means that two adjacent Immobilizers immobilize each other until one is captured or until some other piece relays a move to one of the Immobilizers.

The purpose of the self-capture move allowed to immobilized pieces is to disclose a line of attack on the Immobilizer.

The Immobilizer, like its twin the Longleaper, is taken directly from Robert Abbott's unusual and innovative game Ultima.

King (K)

The King moves and captures one step to any of the eight orthogonally and diagonally adjacent squares. It is a royal piece, one of five in the game; capturing all your opponent's royal pieces wins the game (by convention, the game more commonly ends with checkmate, an unstoppable threat to capture the last royal piece. However, note that the victory conditions for Typhoon are different from those of Orthochess).

The King has moved the same way for almost a millenium and a half.

Special rules govern the promotion of the King. If there is no Emperor on the board (belonging to either player), then the King promotes to an Emperor. However, if either player has an Emperor, the King promotes to an Emperor of Emperors, which is far more powerful than an Emperor.

This rule came about as follows: I wanted to encourage players to try to promote the King, since marching the King across the board is generally risky, and adds to the excitement of the game. The best way to encourage promoting the King is to have it promote strongly. However, if the King promotes to a strong Emperor, the Emperor will be difficult to catch; if both players have an Emperor, the game may be a draw, since neither can pin the oppponent's Emperor down. After a game as long as Typhoon, a draw is hardly a satisfying outcome, so I built into the game a strong disincentive to promote to an Emperor unless you are confident that your opponent won't be able to do the same: if you have an Emperor and your opponent promotes a King, your opponent gets an Emperor of Emperors, a piece of overwhelming power.

This promotion rule means that an Emperor of Emperors won't appear in games of Typhoon very often, unless the player who promoted to Emperor made a serious miscalculation; however, the threat that one player might get an Emperor of Emperors can have a real effect on the course of the game, by preventing promotions to Emperor.

Note that although the reasoning behind introducing the Emperor of Emperors is to try to avoid the situation where both players have equally mobile strong royal pieces, it is possible (although not very likely) for the same player to acquire both an Emperor and an Emperor of Emperors. If your opponent has two royal pieces (after, say, promoting the Drunk Elephant to an Elephant Prince), your Cuckoo or Missionary can convert the opponent's King to your ownership, so that you may have two Kings on the board. In such a case, if you promote both Kings, the first becomes an Emperor and (provided you don't lose your Emperor in the meantime) the second becomes an Emperor of Emperors.

Knight (N)

The Knight is a (2,1) leaper; that is to say, it leaps directly to any space that could be reached by moving 2 spaces along any rank or file, and then one space at right angles.

The Knight is a piece retained from the earliest known forms of chess.

Lantern (La)

The Lantern moves and captures as a Firzan in the two forward directions; it cannot move backwards.

The Lantern, along with its twin the Banner, replaces the Go-Betweens of Chu Shogi. The Go-Betweens move only straight forward and backward, but I thought that being confined to a single file was too limiting a life, so I gave the Lantern a little more freedom.

Lioness (Li)

The Lioness can leap to any square a King could reach in two moves; that is, it is a combination of Wazir, Firzan, Dabbaba, Knight, and Alfil.

The Lioness is inspired by the Chu Shogi piece called the Lion. In addition to moving like the Lioness, the Lion can make two full King-type moves on a single turn, with the ability to capture pieces on both parts of the move, or to move back to the starting square. The Chu Shogi Lion is generally valued at about twice a Queen; the Lioness is distinctly weaker than a Queen on a 16 x 16 board.

The promotion of Goat to Lioness also has a Chu Shogi origin; in Chu Shogi, the Kirin, which inspired the Goat, promotes to a Lion.

Longleaper (Lo)

The Longleaper moves when not capturing like a Queen. To capture, it hops along Queen lines over an opposing piece to an empty space beyond the piece along the same line; the opposing piece is captured. The space immediately beyond the opposing piece on the Longleaper's line of movement must be empty. If there are more opposing pieces along the same line of movement, the Longleaper may continue to capture pieces along that line as long as the square beyond each captured piece is empty and no friendly pieces are interposed between the captured opposing pieces. The Longleaper may land on any empty space along the line of movement beyond the last captured piece.

The Longleaper may never leap an empty space or land on an occupied square.

The Longleaper is extremely powerful when opposing forces consist mainly of widely scattered weak pieces; it can often position itself so that it threatens to capture in several different directions.

The Longleaper is taken directly from Robert Abbott's Ultima.

Marquis (Ma)

The Marquis moves and captures like a Wazir or a Knight.

The antecedent of the Marquis is the Marshall (Rook + Knight) of Christian Freeling's Grand Chess, but the Marshall is too powerful to be a starting piece in Typhoon.

Missionary (Mi)

The Missionary moves like a Wazir, or up to two steps as a Bishop. It cannot capture, but if it ends its move adjacent to an opposing piece along the line of the Missionary's movement, then the Missionary may (but is not required to) convert the opposing piece to a friendly piece.

For example, given a Blue Missionary on a3 and a Tan Pawn on d6, the Missionary may move to c5 and convert the Tan Pawn to a Blue Pawn (it may also leave the Tan Pawn as a Tan Pawn). This makes the Pawn effectively change direction; that is, the transformed Blue Pawn moves northwards like all other Blue Pawns, and does not somehow remember its previous southward orientation from its life as a Tan Pawn.

The Missionary's twin, the Sorcerer, can capture multiple pieces on the same turn, but the Missionary can convert only one piece per turn.

The Cuckoo's ability to change the ownership of a piece is slightly different, since the Cuckoo cannot move and convert in the same turn, while the Missionary cannot convert without moving.

The Missionary's ability to start its move at a distance from the piece to be converted makes it moderately strong, but its low mobility means that it is not really formidable.

Nightrider (Nr)

The Nightrider may move and capture as a Knight; it may also repeat a Knight's move as far as it wishes in the same direction through clear spaces until it reaches the edge of the board, or is blocked by a friendly piece, or lands on an opposing piece, capturing it. In short, the Nightrider is to the Knight as the Rook is to the Wazir.

The Nightrider is a well-known fairy chess piece, introduced to many readers by Anthony Dickins's A Guide to Fairy Chess.

Octopus (Oc)

The Octopus moves one step diagonally, then like a Rook orthogonally, but only in a direction away from its starting square. That is, it cannot reach an orthogonally adjacent square. It can both move and capture on the Rook-like part of its move, but it can only move without capturing to the diagonally adjacent square. That means that the closest square on which it can make a capture is a Knight's move away.

The name "Octopus" for this piece comes from a copy of some unpublished material on a game concept called "Generalized Chess" by the great game inventor Wayne Schmittberger, forwarded to me by Edward Jackman. It wasn't clear from Wayne's description whether his Octopus could actually move one space diagonally or had to move at least as far as a Knight, so I split the difference and allowed my Octopus to move like a Firzan but not to capture like one.

The ultimate ancestor of the Octopus is probably the Giraffe of Timur's Great Chess. Timur's Giraffe moves differently from the piece we usually know today as the Giraffe; Timur's Giraffe moves like the Octopus, but must move a minimum distance of four steps, i.e., at least as far as a modern Giraffe's move.

Otter (Ot)

The Otter moves and captures as a Firzan, or one step forward as a Wazir, or up to four steps to the left or right as a Rook.

The Otter and its twin the Beaver are kin to the Chu Shogi Side Mover; they are difficult to advance, but their strong sideways movement makes them quite useful as defenders.

Overtaker (Ov)

When not capturing, the Overtaker moves like a Commoner. To capture, it may leap an orthogonally or diagonally adjacent hostile piece to capture it, provided that the space immediately beyond (where the Overtaker winds up) is empty.

For example, given a Blue Overtaker on a4 and a Tan Pawn on a5, the Overtaker may capture the Pawn by hopping it to a6.

The Overtaker cannot hop a friendly piece.

Parrot (Pa)

The Parrot has a complex move. It can do any of the following:

The Parrot is derived from a Chu Shogi piece called the Horned Falcon, which moves like the Parrot but only forwards (it moves like a Queen in the other directions). I eliminated the Queen-like movement and extended the forward movement to all four orthogonal directions.

Pawn (P)

The Pawn moves one step straight ahead when not capturing, or one step diagonally forwards (left or right) to capture. Unlike the Orthochess Pawn, the Pawn in Typhoon does not have the option of making a two-step move.

Priest (Pr)

The Priest moves and captures like a Firzan or a Knight.

The antecedent of the Priest is the Grand Chess Cardinal (Bishop + Knight), just as that of the Marquis is the Grand Chess Marshal.

Queen (Q)

The Queen moves and captures like a Rook or Bishop, as in Orthochess.

The promotion of the Stork to the Queen was inspired by the Chu Shogi Phoenix's promotion to Free King. In Chu Shogi, the Free King moves just like an Orthochess Queen, and the Stork was derived from the Phoenix.

Raven (Ra)

The Raven has a complex move. It can do any of the following:

The Raven is derived from a Chu Shogi piece called the Soaring Eagle, which moves like the Raven but only forwards (it moves like a Queen in the other directions). I eliminated the Queen-like movement and extended the forward movement to all four diagonal directions.

Rook (R)

The Rook moves the same as its Orthochess equivalent; that is, it moves when not capturing orthogonally any number of clear spaces, and captures by moving orthogonally across any number of clear spaces to the first space occupied by an opposing piece, which the Rook replaces.

The Rook has moved the same way since the earliest forms of chess.

Salamander (Sa)

The Salamander moves when not capturing like a Queen, up to four steps away; however, it can capture only adjacent pieces, like a Commoner.

The Salamander is fairly agile but not particularly powerful; the best thing to do with it is often to promote it.

A salamander is an amphibian with a lizard-shaped body. Did you know that the largest salamander in the world is the Japanese Salamander? (If that's a reference to Chu Shogi, it's an oblique one.)

Scirocco (Sc)

The Scirocco moves and captures one step orthogonally or any number of steps diagonally, that is, as a Wazir or Bishop. This is the same as the move of the promoted Bishop (or Dragon Horse) in Shogi; the Dragon Horse also exists as an unpromoted piece in Chu Shogi.

This piece appears as an initial piece in the game of Scirocco, but only as a promoted piece in Typhoon.

Silver General (SG)

The Silver General moves and captures like a Commoner, but not orthogonally sideways or backwards; in the middle of an empty board, it can move to any of five squares.

The Silver General is a piece from Shogi (as well as Chu Shogi). It appears to have replaced the less powerful Alfil in many chess variants in the eastward branch of chess evolution; the same piece is found today (in what Westerners think of as the Bishop's slot) in the native chess variants of Burma and Thailand.

Sorcerer (So)

The Sorcerer moves like a Wazir, or up to two steps as a Bishop. It cannot land on an opposing piece, but if it ends its move adjacent to an opposing piece along the line of the Sorcerer's movement, then the Sorcerer may (but is not required to) capture the opposing piece and all contiguous opposing pieces along the same line of movement. (The Sorcerer must capture all the pieces it can, or none; it cannot capture only some of the pieces eligible for capture.)

The type of capture the Sorcerer performs is sometimes called "capture by approach".

In the unlikely event that opposing pieces are lined up just right, the Sorcerer can capture as many as ten pieces in a single turn.

For example, given a Blue Sorcerer on a3, a Tan Pawn on c3, a Tan Camel on d3, and a Tan Knight on f3, the Sorcerer can move to b3, capturing the Pawn and Camel (it may also leave the Pawn and Camel uncaptured). It cannot capture the Knight because there is a gap between the Knight and the Camel.

The Sorcerer's ability to end its move on a square other than one previously occupied by a captured piece and its ability to capture multiple pieces at a time may make it sound powerful, but its mobility is low, so it's not as tough as you might think.

Spider (Sp)

The Spider moves one step orthogonally, then like a Bishop diagonally, but only in a direction away from its starting square. It can both move and capture on the Bishop-like part of its move, but it can only move without capturing to the orthogonally adjacent square. That means that the closest square on which it can make a capture is a Knight's move away.

The Spider is the diagonal counterpart of the orthogonal Octopus, and like the Octopus, was taken from an unpublished piece by Wayne Schmittberger.

Squirrel (Sq)

The Squirrel moves and captures as a Dabbaba, Knight, or Alfil.

The Squirrel is among the many interesting pieces that appears in Anthony Dickins's A Guide to Fairy Chess. Dickins ascribes its invention to N. Kovacs of Budapest.

Stork (St)

The Stork moves and captures by leaping two steps diagonally (like an Alfil); it may also capture one square orthogonally, but not move there without capturing. When moving two steps, it leaps any intervening piece without capturing or being blocked by it.

The Stork is a weakened form of Phoenix, a piece from Chu Shogi. The Phoenix can both move and capture one step orthogonally.

Tadpole (Ta)

The Tadpole moves and captures as a Firzan or as a (3,0); that is, it can move to an adjacent square, or leap to a square three steps away orthogonally or diagonally (ignoring any intervening pieces). It may also capture as a Wazir, but not move without capturing as a Wazir.

The Tadpole is a slightly weaker version of the Scirocco Frog. Since the Pawn doesn't go through a complex promotion cycle in Typhoon, I figured it shouldn't promote quite as strongly.

Tiger Prince (TP)

The Tiger Prince, a royal piece, moves when not capturing as a Commoner, and captures like Dabbaba or Knight.

The Tiger Prince can capture on more spaces than a King, and so is better than a King as an offensive piece; however, a King can single-handedly checkmate a Tiger Prince.

Toucan (Tou)

The Toucan has a complex move. It can do any of the following:

The Toucan is a variation on the Parrot; whereas the Parrot's second step is either 0 or 180 degrees from the direction of its first step, the Toucan's second step makes an angle of 90 degrees to its first.

Typhoon (Ty)

The Typhoon moves and captures like a Firzan or an Alfil, or like a Rook up to three spaces. When moving like a Rook, however, it does not have to stop when it makes a capture; it can continue in the same direction as long as it does not hit a friendly piece or exceed the three-step limit. This means it can capture up to three pieces in a single turn.

Since the game of Scirocco includes a piece with the same name as the game, I thought I'd put one in this game as well.

The Typhoon is not especially mobile, but its ability to capture multiple pieces or to keep moving after a capture make it fairly valuable.

Undertaker (Un)

When not capturing, the Undertaker moves like a Commoner. To capture, it moves on step (like a Commoner) away from an orthogonally or diagonally adjacent hostile piece; if the hostile piece lies along the line of the Undertaker's movement, it is captured.

For example, given a Blue Undertaker on a4 and a Tan Pawn on a5, the Undertaker may capture the Pawn by moving to a3.

An Undertaker cannot move to an occupied square.

Vulture (Vu)

The Vulture captures like a Rook and moves without capturing like a Bishop. It may also capture like a Firzan and move without capturing like a Wazir, so that it can both move and capture on adjacent squares.

Wagon (Wa)

The Wagon moves and captures like a Rook, except that it may not move to or capture on an adjacent space. However, the Wagon may be blocked by a piece on an adjacent space. For example, if a Blue Wagon is located on a1, and Tan pieces are located on a2 and a3, then the Blue Wagon cannot move along the a-file or capture either Tan piece.

An adjacent-space restriction similar to the Wagon's is also found in the Talia, or Scout, in Timur's Great Chess (the web page translates "Talia" as "Picket"). However, the Talia moves as a restricted Bishop, rather than a restricted Rook.

I wanted a weakened form of the Rook so that the Rooks would not dominate the board too early. Of all the spaces a Rook can move to, the immediately adjacent spaces are probably the most important (at least until the board opens up), so removing the ability to reach an adjacent space makes the Wagon weaker than the Rook by more than you might expect (although less so on the 16 x 16 Jupiter board than on smaller boards). I chose the name "Wagon" because its meaning is similar to "Chariot", the original name of the Rook; wagons are generally less maneuverable than chariots, so the name seemed appropriate.

Wazir (W)

The Wazir moves and captures one step orthogonally.

The name "Wazir" (Arabic, "vizier", meaning a government minister or adviser), like the name "Dabbaba", was used for pieces with different moves in different medieval Islamic chess variants. The Wazir's move in this game is the one commonly used today, and is the same as in Timur's Great Chess.

The Wazir has sufficiently low mobility that it is seldom worthwhile advancing it, and it often winds up as a defender of the King in the endgame.

Wildebeest (Wi)

The Wildebeest moves and captures like a Knight or Camel.

The Wildebeest, also called the Gnu ("gnu" being another word for "wildebeest"), is among the pieces described in Anthony Dickins's A Guide to Fairy Chess. Wayne Schmittberger liked the piece well enough to name a chess variant, Wildebeest Chess, after it.

Zag (Za)

The Zag moves and captures like a Firzan or Alfil; in addition, it may leap an orthogonally adjacent hostile piece to capture it, provided that the space immediately beyond (where the Zag winds up) is empty. The Zag may not move orthogonally when not capturing, however.

I made up the name and the move of this piece for the game of Scirocco. The Zag is the diagonal counterpart of the orthogonally moving Zig.

Zebra (Z)

The Zebra is a (3,2) leaper; that is to say, it leaps directly to any space that could be reached by moving three spaces along any rank or file, and then two spaces at right angles. This makes it an even more extended "Knight" than a Camel.

Because of its long reach, the Zebra is fairly weak as leapers go; it has relatively few squares on the board from which it exercise its full power.

Zig (Zi)

The Zig moves and captures like a Wazir or Dabbaba; in addition, it may leap a diagonally adjacent hostile piece to capture it, provided that the space immediately beyond (where the Zig winds up) is empty. The Zig may not move diagonally when not capturing, however.

I made up the name and the move of this piece for the game of Scirocco. The Zig is the orthogonal counterpart of the diagonally moving Zag.

Latent Abilities

Some pieces (the Doubler, Fiery Dragon, Immobilizer, and Poisoner) have "latent" abilities; that is, they can affect other pieces without being the piece that makes a move on the current turn. Each of these abilities has a set precedence with respect to the others, to avoid ambiguity in the game.

A Fiery Dragon effectively trumps an Immobilizer. That is, whether a Fiery Dragon moves to a space next to an opposing Immobilizer or an Immobilizer moves to a space next to a Fiery Dragon, the Immobilizer is captured and the Fiery Dragon is not immobilized.

An opposing Immobilizer prevents a Doubler or Poisoner from moving, but the Doubler's or Poisoner's ability to double or poison is not affected. However, if a piece is under the influence of both a Doubler and an Immobilizer, it is immobilized, not doubled. For example, given a Blue Immobilizer on a2, a Tan Doubler on b2, a Blue Guard on b4, and a Tan Rook on b1, the Doubler and Rook are immobilized, but the Guard may make a double move because it is under the influence of the (immobilized) Doubler.

Poison

Poison is a temporary or permanent characteristic of a piece that can cause an opposing piece to be removed from the board in circumstances where it ordinarily would remain on the board.

The Deadly Nightshade is permanently poisonous; other pieces become temporarily posionous when under the influence of a (friendly or opposing) Poisoner.

Poison works as follows: if a piece of the opposite side from the poisonous piece ends the turn on the same space where the poisonous piece started the turn, the opposing piece is removed. In most cases, this means the opposing piece will have captured the poisonous piece, but that is not necessary in order for a poisoning to occur. For example, if a Hummingbird swaps places with an opposing poisonous piece, the Hummingbird is captured. If the Hummingbird in question is also under the influence of a Poisoner, both pieces are captured.

Poison affects only pieces unfriendly to the poisonous piece; for example, a Hummingbird exchanging places with a friendly poisonous piece is not poisoned.

A piece that captures a poisonous piece but does not end the turn on the poisonous piece's square is not removed, so that a hop-capture of a poisonous piece does not cause a poisoning. A piece that makes two consecutive moves under the influence of a Doubler may land on a poisonous opposing piece at the end of its first move, but does not suffer poisoning if it moves to a nonpoisonous location by the end of the turn.

Promotion Rules

A piece may promote at the end of any move it makes that starts or ends (or both starts and ends) in its owner's promotion zone. Blue's promotion zone is ranks 11 through 16, or Tan's pawn row and beyond; Tan's is ranks 1 through 6, Blue's pawn row and beyond.

Promotion is always optional. Even when you move a Pawn onto the last rank, you are within your rights (if not in your right mind) not to promote it.

Promotion cannot occur when a piece moves using a movement capability relayed by another piece, e.g., a Dervish, Harpy, or Hummingbird (a Hummingbird may itself promote if it changes place with another piece, provided that the Hummingbird starts or ends its move in the promotion zone). If a piece to which a movement capability could be relayed already has the movement capability in question (as in the case of a Goat leaping orthogonally over a Dervish), the piece is considered to be moving under its own power, and may promote if its move starts or ends within the promotion zone.

A piece is not entitled to promote when a Cuckoo or Missionary changes its ownership within the promotion zone; the piece itself must make a subsequent move (starting or ending within the zone) in order to promote.

If an unpromoted piece with relay power (e.g., a Dervish) located within the promotion zone relays a move to another piece, the piece with relay power does not thereby gain the right to promote on that turn. Similarly, a Cuckoo changing the ownership of a piece within the promotion zone is not entitled to promote.

Victory Conditions

You lose the game (and your opponent wins) if any of the following occurs:

It is not, strictly speaking, illegal to move your last royal piece into check. It is certainly foolish, though. On the other hand, there is no constraint on moving a royal piece into check when you have more than one royal piece; in fact, there are situations where it is advantageous to do so.

Note that these rules make stalemate a loss for the stalemated player, not a draw.

The Bare King rule means that when you are reduced to two pieces, both are effectively royal.

You can move your King into what looks like check if it captures your opponent's last piece, since you win the game before your opponent can recapture.

Repetition

It is illegal to make a move that causes a given game situation to occur a third time in the same game. Two game situations are considered the same if the same types of pieces are in the same places and it is the same player's turn to move.

Specifically, repetition does not result in a draw; one player must make a move that leaves the cycle of repeating moves. When a player is to move but has no move that would not cause an illegal repetition, that player loses the game.

As an example of this repetition rule, consider how it would apply to a trivial game played on a 2 by 3 board, with rules the same as Jupiter except as specified. The game starts with a White King on a1 and a Black King on b3; in this microscopic chess variant, there is no Bare King rule (so the game is not already over at the beginning). This game must proceed as follows:

1. K-b1 K-a3
2. K-a1 K-b3 ; 2nd occurrence of initial position
3. K-b1 K-a3
4. K-a1

At this point, the move 4. ... K-b3 would recreate the initial position again; this would be the third occurrence of that position, so the move is not legal. If this variant allows a King to move into check, Black must do so (with 4. ... K-a2 or 4. ... K-b2), in which case White will capture the King and win on the next move; if this variant does not allow moving into check, then Black has no legal move, and loses immediately.

Draws

If you have read the above rules carefully, you will realize that any game of Jupiter played to the bitter end cannot result in a draw. Even if neither player is checkmated or reduced to a single royal piece, the repetition rule ensures that the game will end, because the number of possible board positions is finite, and each position cannot occur more than twice. When no more positions are available, the player whose turn it is will lose.

Players may, however, agree to a draw if they are so inclined.

It is conceivable that both players may be reduced to a small number of weak but highly mobile pieces, so that the repetition rule must be invoked to determine who wins the game.

I'm not going to pin down exactly when agreeing to a draw is advisable. If you want to spend the rest of your life playing a single game, fine by me. (In the extremely unlikely event that Jupiter is ever played in a serious tournament, tournament organizers will want to come up with a more specific rule.)

Strategy

I have not playtested Jupiter at all. However, I'd guess the following:

Notation

Several of the types of moves in Jupiter are unconventional and pose a slight problem for notation. Some possible points of difficulty:

Where's the Zillions File?

Zillions of Games! is the remarkable computer program from Zillions Development that will play with you any game you can describe to it (using a special programming language called ZRF).

The Zillions file for Jupiter is under development; I expect it to be a challenge for Zillions as well as for me. With any luck, I will have it done some time this summer (the summer of 1999).


Written by Adrian King.
WWW page created: 1999. Transferred to the chessvariants.com on 12 Oct 2001.