Ratings & Comments

Peter,

I think you're right--bare king rule should not apply.  There will be some
interesting endgames with stalemate as a win. For example, K and R vs K
can be a win if the pieces are in the right realms, such as R holds enemy
K on the last rank as friendly K moves to stalemate. 

I rather like the sound of Separate Realms Chess.

R on seventh rank and bare enemy K on eight rank IS stalemate! How did I
overlook that?

It is not sufficient for the king to be on a secure
file or rank, to force a draw against king and oddling
it has to be in the secure corner.

Here is how to mate the black king with king and 
oddling:

White: Og7,Kh6  Black: Kf8

First, White brings its king to h8, than it pushes 
its king forward using zugzwang until it reaches d8.

White forces the Black king to a8. Now the finale:

Kc7!  Ka7
Og5   Ka6
Oe5   Ka7
Oa5++

J'org Knappen

With the weak King (FcW) and stalemate as a win, the proposed game isn't a
bit drawish. K vs K on the same color is a forced win for whichever side
can get the opposition. (This is a simple calculation: if the coordinate
differences between the Kings are odd, for example a1 vs d6, the player on
move wins; if the differences are even, the player not on move wins.)

Similarly, if the Kings are on the same color K and any piece vs K is a
forced win unless the bare K can capture the piece--the stonger side can
use the mobility of the piece to avoid zugzwang.

Peter, if you are willing to do it I would appreciate it very much.

Jorg, neat mate! Possibly Separate Realms Chess is playable with an
orthodox king, though I still prefer the weaker king for the game. I
wonder if the starting position for the mate can be forced though--I think
a defensive stategy for this game will be to keep the king away from the
edges to maximize its mobility.

in addition to what mike said, i know those links are in fact correct,
rather than 'not going where they're supposed to go.'  the webpages they
are linking to no longer exist. at chessvariants.com, they usually put a
note on a webpage that contains an outgoing link that it doesn't work
anymore, but this can be difficult to keep updated on something as huge as
chessvariants.com

Thanks Peter, that's it! Probably the taz article was 
a direct translation of that text, including the Foucault theme.

I think, it's worth an external link on the link pages.

--J'org Knappen

I'd have to search around for games.  off the top of my head, i'd also
definitely recommend rococo and ruddigore by aronson.  i also recommend
schizophrenic chess, altho i don't know if we want to overlap this with
the 84 square contest.  i might also suggest my own game crazy38s.  what
else... captain spalding chess by betza.  if we want a 3D game, i'd
suggest millenium 3D by a'gostino or exchequer by hewson, since they can
both be played in about the same amount of time it takes to play a
standard chess game.  i am also a big fan of rennaissance chess by eric
greenwood.  i also like the the commercial game quantum II, III and IV.  i
also like looneybird, even tho freeling is no longer big on it.

sorry this message wasn't as organized as aronson's, nor does it link to
the games.

I did a list of eight, trimmed from a first list of nearly 40, to show how
a set of games might feature a wide range of styles and options.  In
alphabetical order:

Chigorin Chess (Betza)...non-matching forces
Extinction Chess (Schmittberger)...new objective
Magician Chess (Whittle)...small board, new piece, board alteration
Not-particularly-new Chess (Aronson)...add-a-few-squares-and-new-piece(s)
genre
Sudden Death Chess (Chatham)...simple rule change with radical
implications
Take Over Chess (Quintanilla)...small board, different captures, new
piece
Triplets (Sobey)...multi-moves, alternate objective
ximeracak. (Overby)...sweeping piece changes to standard set

I share David's nervousness about larger games, although Modern Chess,
21st Century Chess, and Chess on a Longer Board With a Few Pieces Added
are on my long list.  So are Crazy 38s and Separate Realms (from other
people's lists).

I would like to feature some prizewinners from our contests, and while the
tournament should feature lesser-played designs it might not hurt to have
a better-known game or two in the mix.  Losing Chess is another I'd
consider for that role.

I just checked Peter's linked recommendations, and I shake my head.  There
is so much good stuff there, and elsewhere on CVP, that you cannot track
it all.  :)

I wonder what Ralph Betza, in particular, might suggest?  He's been at
this a while...

I noticed Ben's comment on the 84-space contest.  Aside from the fact that
we won't want many games that size in any case, I don't think that any
game being voted upon in 84-spaces should be eligible for this event. 
Even its presence in a poll to pick the games could affect the contest
voting.

We may miss a good game that way, but if this flies there's always next
year.

There certainly are a lot of worthy games to consider, and this fabulous
website makes it both harder and easier to decide.  Harder because so many
interesting games can be found here.  Easier because you can read their
rules at a click, and in some cases read what others have thought.  I
looked at the games suggested by others, and a few games I am partial to
myself, and came up with this list:

Among newer variants:
  Rococo certainly looks very interesting -- perhaps a better Ultima.
  Separate Realms is new and promising enough to warrant some play.
  Take Over has an interesting mechanic that I'd like to see explored.
  Crazy 38s is so original and innovative that it begs to be played.
  Caissa also has a unique and interesting mechanic and I've always
wondered how well it plays.
  Flip Shogi looks interesting.
  Cannon Shogi looks likes an interesting shogi variant with added power
on the board.

Among large variants:
  Centennial Chess looks fascinating, and for the adventurous, perhaps
even Millenial Chess by the same inventor.
  Some form of Grand Chess seems like a good idea -- I think perhaps
Grander Chess might even be the best choice.
  Reniassance Chess also looks to be a worthy entry in the large variant
category.

Among hexagonal games:
  Hexagonal Chess by Shafran has always struck me as perhaps better than
Glinski's game -- it would be intersting to find out.
  Hex Shogi by Duniho -- perhaps a small board variant is called for, but
that all look intriguing to me

Among established variants:
  Extinction Chess has always struck me as a great, simple idea.
  Chessgi is an acknowledge classic, a great game.
  Rifle Chess has always intrigued me.

And I guess I better stop there, since I've already listed more than 10. I
could easily go on.  I'll resist the temptation to list my only TCVP entry
(Biform Chess) since I've recently had second thoughts about the starting
array.  And it's too bad that this is all happening just a few weeks
before my own new games come out, but I suspect that interest in them will
be a little limited anyway, since they're both big-board variants (10x10
and 11x11) and one of them is very unusual and Ultima-like.

What kind of time frame has been proposed for these games?  A move per
day?  Will there be a time limit?  I'd love to play, but some days I'm so
swamped I can't afford to think about chess.

Time limits are the headache of correspondence chess.  Sigh.  I, too, am
spoiled by Richard's PBEM server.  The Omega Chess tournament there is at
G/180 days (30 days vacation with notice allowed), and that G/180 gets
counted to the minute and second by the central server.

Obviously we don't have that option.

Suggestions for how to best count a G/XX time limit are welcome.  I'd like
to see a year maximum on the games, and expect to see more small variants
than large for that reason (and the fact that we've had a lot of small
variant design contests!).

An absolute time limit of Y days for any individual move, with one warning
and a notice provision for vacations, might also work in lieu of the
above.

I think I like Glenn's idea of X days per move, with one warning before
forfeiture, and suspension upon proper notice of vacation, illness,
personal matters, etc.  Since this tournament should be viewed as a
friendly one between like-minded variant players, the rules shouldn't be
too restrictive.  I think 3 days per player-move should cover most
situations other than the aforementioned major ones, and it means that in
a year all games that take less than 60 full moves will be finished.  In
reality, games even much longer can probably be finished since players
will in most cases not take 3 days for every move.  For some games, and on
some days, I know that I will be able to play several moves if my opponent
is agreeable.

Obviously, the ten games should be Chess with Different Armies, Feeble
Chess, Tripunch Chess, Half Chess, Amontillado Chess, Progressive
Cambiamarce DemiChess, Torus Peacebump Punch Chess, Cloud Chess, All Go
Together Chess, Nemoroth, and Alice's Chessgi.

I tend to pick from games i'm more familiar with....

I'm afraid I don't recognize some of those.  :)

Maybe we have to do a Ralph Betza tournament some time.  Then a Peter
Aronson tournament the following year.  Maybe Parton or Schmittberger or
Freeling the year after that.

There is no such rule.  The maximum allowable number of moves in such a
position is 50, with certain conditions. (See the laws for more details
about the fifty move rule.)

The figure thirteen probably comes from end game studies. If I remember
correctly, King and Rook vs bare King can mate in 13 moves or less
starting from any legal, non-stalemated position.  I belive the
corresponding figures are 8 for King and Queen vs bare King, 14 for King
and 2 Bishops (on opposite colors) vs bare King, and 49 for King, Bishop,
and Knight vs bare King. [Someone please correct me if my memory is
faulty.]

But all the numbers I quoted assume perfect play--the laws do not require
perfect play. (Except in the last case, but truthfully I don't know how to
force mate with a Bishop and Knight in 1000 moves, nor has anyone ever
done it to me.)

I prefer regular-sized or large variants to small ones, so I'd not like to
see the contest limited to games of 38-41 squares, though I'd certainly
not object to some of those games being included.   I'd rather see the
slate of games for any given year be eclectic -- some small, some
normal-sized, some large, and from a variety of inventors or sources.  You
get to experience more interesting games that way, I think, and no one
gets left out because all of the games in a given year are not to his/her
taste.

It looks like I'll be the editor in charge of the first tournament.  Right
now I have compiled, with plenty of suggestions, a list of 42 games to
pick from.  They break down around 50% regular board size, 33% smaller,
16% larger.

I am constructing a poll to allow folks to vote on any of those games they
would like to see in, and indeed to suggest others.  The set of games to
be used _in 2003_ will be picked by the staff here guided by the polls. 
We want a mix of old, new, big, small, etc.  Variety is key the first time
out.

When and if the first tourney succeeds, I'd love to see 'thematics' later,
much as we have held a variety of design contests.  The linchpin issue is
simply whether we can get players.  I'd be happy with 10, but would love
20 or more.  And picking good games is a prerequisite to getting players.

And I agree with the comment that there are so many good games it's hard
to get agreement on a list.  That's why I suggested this; lots of good
games languishing in obscurity.

Please keep the feedback coming...

i see quite a few things have been posted on this subject while i was out
of town this weekend.  i would also caution against too many large
variants for the same reason that they take much longer to play.  in a
previous comment i listed a bunch of larger variants as possibilities, but
i wasn't suggested we play all of them, just that they were all good
possibilities.  i would also be careful about small variants that are
chosen.  as both a game designer and judge, i know that designing a small
chess variant is much more difficult than designing a medium or large one.
 i found very very few small variants that i was truly impressed with, and
even fewer that were so well designed that they would not have been
improved if the ideas had been extended to a larger game.  even some of
the games that ranked high in some of the contests i found to be quite
weak.

Wonderful idea! As far as the timing, either the 3 days per move or the
total day limit idea would work, I think. Total days used could be tracked
manually with each PBEM exchange. As far as a list of games, here's some
ideas:
- Chaturanga (worthy grandad of Chess)
- Jumping Chess (interesting capturing mechanic)
- Glinski's Hexagonal Chess (hex mechanics)
- Makruk (wonderful old and contemporary variant)
- Take Over Chess (I'm partial to it!)
- Chess on a Longer Board (its that Wall)
- Xiangqi (another worthy variant)
- Mulligan Stew Chess (crazy but fun)

I need to play with this.  It's quite an idea.

I wonder if the King shouldn't be like any other piece, even in check; if
you're in check, have no card to move the King, and can't defeat the check
otherwise it is mate.

The concept will map with interesting results to a lot of variants that
use the ordinary 8x8 and 32 pieces.  The cards might even work best with a
form other than orthochess.

Peter, you think too much!  :)

Just had another thought...a 10-card version with five cards each for King
and Pawn, two cards each for others, with the Wild card.  Or 9 without the
Wild card.  The optimum card mix, as you astutely noted, may not yet be
known.

KQ KB KN KR KP PQ PB PN PR (Wild)

Does castling require one card, or two, as you see it?  I vote one, a King
card, since officially castling has long been viewed as a move of the
King.  But I could go either way.

A 19-card set sounds like a plan...White with nine, Black with nine plus
the Wild card, no card used on White's first move.

I can see some potential for endgame draws, where mating material is
hindered by a lack of sufficient cards to make the moves.  :)

Castling as a King move is a good idea, I think.  The endgame.  Hmm.  A K +
Q vs K endgame could be stymied by the player with the bare King holding
on to the KQ, PQ and (Wild) cards.  I wonder if some additional mechanism
is called for.  Of course, it needs to be seen if this game comes down to
situations like that.  Pawns are relatively mobile, and because there are
many cards that let Pawns move, they defend each other with greater
effectiveness than other pieces.  It seems to indicate that Pawnless
endgames may not be as common as in usual Chess.

Peter,

It seems like another new game is about to be born in the comments system.
 It looks like a very good one.  If drawishness is a problem because of
hoarding cards as you suggest it may be, perhaps the answer is to use a
stronger than FIDE army to compensate for the difficulites of moving.

K and Amazon vs K should be more winnable than K and Q vs K as fewer moves
are needed=card hoarding is less effective. But I would really prefer the
FIDE army if the game is playable with it.

Perhaps you might consider buying an Omega Chess set
(http://www.omegachess.com), which uses a 10x10 board with extra corner
squares which could be ignored for the 10x10 gaes you want to play.

I have two observations.  First is that I think wide boards actually
increase the relative value of diagonal movers, not orthogonal ones. 
Consider a very long narrow board.  It will take a diagonal mover many
moves before it can hit a square on the opponent's half of the board,
whereas an orthogonal mover can do so on turn one.  On a wide board, the
diagonal mover has more squares from which it can attack squares in the
opponent's camp.

Secondly, I agree about unit density.  I am currently working on a large,
complex ultima-like game with powerful unorthodox pieces.  I found that
the game only works on a 10x10 board with three rows: one row of pawns,
one row of guards (with value intermediate between pawns and pieces but
without the pawn's ability to promote) and one row of pieces.  Unit
density is 0.60.  Immediate development is slower than in orthochess, but
because units are more mobile than orthodox pieces, the game heats up
pretty quickly.  All of the games I have playtested, and there have been a
lot, have ended in less than a hundred moves.  The game isn't quite ready
for posting to these pages but if anyone is interested in seeing what I'm
talking about and wants to email me, I can send them a 'beta' version. 
It's quite playable and interesting, I think.  But you'll only like it if
you like games that are more complex and somewhat wilder than orthochess.

For comparison's sake, I quickly calculated some piece densities:

Shogi     49.4%
XiangQi   35.6%
Timur's   50.0%

The density of any 9x9 variant with an extra piece is 44.4%

ok, i'll have to come back and read more carefully later, but one thing i
noticed is something to the effect that wider boards help increase the
value of diagonal movers more than orthogonal movers.  i have had no
experience that would even remoately back up such a claim.  in david
short's doublechess, a game in which the board is 16x8, the bishop is
severely weakened by the width of the board.  it's well-known that
increasing the board size weakens the knight, but in doublechess the B is
hurt almost as much as the N by the board change (comparing to 8x8).  the
fact that it is more likely to attack the opponent's camp in 2 directions
rather than 1 is small compensation for the fact that it often takes 10
moves or move to get the bishop from side of the board to the other.  the
rook, on the other hand, is not affected at all.  in fact, when studying
the relative values of pieces on different sized boards, it is my claim
that all other things being equal, the rook is the most consistent piece
from board to board, and should be the baseline against which other pieces
are measured.

The measurement that was used by Gabriel Vincente Maura to justify the
design of his variant, Modern Chess (Ajedrez Moderno), 
http://www.chessvariants.com/large.dir/modern.html
is kind of interesting.  This is taken from the booklet that came with my
Modern Chess set, 'Mathematical Thesis of Modern Chess', 50 p., 2nd
English Edition Revised, 1974.

He defines the maximum mobility of each piece as the number of squares it
can move to from its best position on the board, that is:

K=8, Q=27, B=13, N=8, R=14, P=2

The maximum relatve mobility for the total of each player's pieces is the
sum of the maximum mobilities of all the pieces, divided by two, because
there are two players.  Thus:

(K+Q+2B+2N+2R+8P)/2 = (8+27+26+16+28+16)2 = 60.5

He defines the maximum mobility that the chessboard offers simply as the
number of squares.  He wants the maximum relative mobility of the pieces
(60.5) to be equal to the maximum mobility offered by the chess board
(64).  Since the numbers aren't equal, he declares FIDE Chess to be
defective.  Needless to say, for Modern Chess, with the addition of the
Marshall, both numbers work out to 81.

Some example calculations for other variants:

                  'mobility'   board
Grand Chess           98        100
Timur's Chess         86        112
Xiang Qi              59.5       90
Shogi(unpromoted)     45.5       81
Shogi(promoted)       75         81

I believe that this is little better than numerology, but it's still fun
to play with.

I think Gabriel is on the right track but needs an improved methodology.  I
would suggest using Betza's crowded board mobilty calculations.  To get
middle game figures, deflate the piece count by 40% and then calculate the
piece density.  For FIDE chess this gives a deflated piece density of 30%
and a square emptiness probability of 70%.  Then using these numbers
calculate the croweded board mobility of one army (for divergent pieces
such as pawns, just use the average of the mobility of the capturing and
non-capturing moves). As it happens this is quite close to 64 for FIDE
chess--so lets simplfy and say that that it is exactly 64 for a ratio of
mobility to number of squares of 1.0.

Having calculated the crowded board mobility of the army divide the square
of the number of squares by the mobitity. For FIDE chess, this is 64
squared divided by 64 = 64.  For a hypothetical 100 square game with a
whole army crowded board mobility of 125, this is 100 squared divided by
120 = 80, while an 81 square game with a whole army mobility of 72 = 91
1/8.  I would predict that the first hypothtical game would have a typical
number of moves close to FIDE chess than the second, even though it has
more squares. 

Final results significanlty greater than 64 indicate games that play
slower than FIDE Chess, results significantly less than 64 indicate games
that play faster than FIDE Chess.

Taking two real games as examples:

Betza's Tripunch Chess would play faster than FIDE Chess even if it were
played on a 10 by 10 board,

Feeble Los Alamos Chess will play slower than FIDE Chess even though it is
played on a 6 by 6 board.

There is no real need to do the actual calculations for purposes such as
time limits for tournaments--a good guess as to whether the game is faster
or slower than FIDE chess is adequate.  The relevant factors are number of
squares, piece density, and strength of pieces.

My s[w]eeping switchers army for chess with different
armies features three pieces with assymetric retreat.
All of them are bent riders: The panda (aka slip rook),
the erl queen (aka slip queen) and the unicorn.

Another one is the mao (xiangi horse) which is not a bent
rider.

--Jörg Knappen

The bent riders and lame leapers (like the Mao) are part of a larger class
that might be called 'multi-movers'.  These are pieces that can make two
(or more) geometrically different moves in the same turn.  The gryphon
moves as a Ferz and then (optionally) as a Rook; the Mao moves as a Wazir
then (mandatorily) as a Ferz. Any such piece will have the asymmetric
retreat property if the order of move types is not reversible. If the
gryphon could move Ferz then Rook or Rook then Ferz it would not have the
asymetric retreat property (and would be immensely powerful).

True leapers such as the Knight in a sense might be said to have the
asymmetric retreat property but it is irrelevant as they can jump over
occupied squares--I prefer to think of a leaper's move as a direct
point-to-point move that does not pass over interventing squares, in which
case the Knights retreat is not asymmetic.

I believe that multi-movers are the only type of pieces which have
symmetric movement patterns but asymmetric retreat. (OK everbody, please
prove me wrong if possible!)

well, besides multi-movers, leaping pieces such as grasshoppers have
symmetric move patterns but assymetric retreat.  and xiangqi cannon has
assymetric retreat when capturing but not when moving, which is one of the
things that makes it such a neat piece (and difficult to get used to).<P>

and incidentally any piece that move differently forwards than backwards
(these pieces don't have symmetric move patterns, at least not about the
x-axis) is going to have assymetric retreat.  this includes lots of betza
pieces such as fBbR, fRbB, etc etc (i could go on and on) and shogi pieces
(which can of course be easily described in betza notation) such as the
gold, silver, copper generals, the white horse and the whale, etc etc.

Thanks, Ben.  Cannon type pieces of course have asymmetic retreat (though
these could be arguably defined as a subtype of multi-movers). Indeed the
Grasshopper and the Cannon when capturing have a stronger form of
asymettric retreat.  Some definitions:

1. High-power Symmetric Retreat--the piece can alway return to its
starting square on the next move by reversing its path (unless prohibited
by the need to meet check, etc.) Example:  Knight. Nb1-c3 can always be
followed by Nc3-b1.

2. Low-power Symmetric Retreat--the piece can return to its starting
square on the next move by reversing its path unless the opponent has used
his turn to block it.
Example: Rook.  Rc3-h3 can be follewd by Rh3-c3 if opponent has not moved
a piece to d3,e3,f3 or g3.

3. Low-power Asymmetric Retreat--the piece cannot reverse its path but may
be able to return to its starting square on the next move if the alternate
retreat path is not blocked. Example: Gryphon.

4. High-power Asymmetric Retreat--the piece cannot return to its starting
square on the next move unless the opponent moves to facilitate it.
Example: Grasshopper.  Gc3-c7 cannot be followed by Gc7-c3 unless the
opponent moves a piece to c4.

Thank you all for your replies.

Might be interesting to have a large variant built on the general theme of
asymmetry: some pieces would have the asymmetric retreat property but have
symetric move patterns, some would also have asymmetric forward and
backward moves, some with asymmetric left and right moves, some with
divergent captures, etc. Perhaps a 11 by 11 game with strong pieces and a
strong, asymmetric King.

11 by 11?  Shouldn't a game with an asymmetry theme be played on an
asymmetrical board? :-)

Perhaps the 43-square contest would be perfect for an Asymmetry Chess...

I like the idea of the large board.

In addition to the general game with the ability to select armies, I feel
that it might be nice to define a game with preset armies and a
distinctive name as a particular case of the general format so that a
collection of games could hopefully be produced by various players.

Here's the rule from our FIDE laws page
(http://www.chessvariants.com/fidelaws.html):

10.10
The game is drawn, upon a claim by the player having the move, when the
same position, for the third time: 
(a) is about to appear, if he first writes the move on his scoresheet and
declares to the arbiter his intention of making this move; or 
(b) has just appeared, the same player having the move each time. 
The position is considered the same if pieces of the same kind and colour
occupy the same squares, and if all the possible moves of all the pieces
are the same, including the rights to castle [at some future time] or to
capture a pawn 'en passant'.

Hi David,  thank you for your reponse.  Then, this rule (10.10) may not
involve any check's.  I really thought it revolved around checking the
King.  I guess not...    ...thanks again.

Legally, triple repetition does not require any checks. However, by far the
most common triple-repetiton draws are those involving perpetual check. I
have never experienced any other type in any game I've played or
observed.

In older verisons of the FIDE laws, perpetual check was a drawing
condition in its own right--then someone observed that pepetual check
would alway eventually lead to triple repetition, allowing the laws to be
simplified.

Oh, wait a minute -- you're trying to end up with your King not attacked.
I don't think that's been done.

If this game already exists, I can't find it. Sounds like it would work
well as each player would have to balance guarding the enemy king vs.
attacking the enemy pieces. I propose we call it Royal Hostage chess.

Here's another, similar idea:

Royal Hero chess

Standard setup.
The first player to do any of the following, wins:

1. Checkmate the opposing King, or
2. Make a move that takes his King out of check
3. Bare his opponent's King

Kings may move into check.
Kings cannot be captured, but may capture.

Hi Joerg,

I assume in German 'official' names for Ultima pieces does not exist.
Each author tries to find the best adaption.  The German version of
Zillions used names that differ from my inventions. I wrote a small
article for the magazin 'Computer-Schach und Spiele'. Please look to
'http://www-user.tu-chemnitz.de/~apf/Gnaax/CV/Ultima/ultima2.html'
for the content.

Friendly greetings,
Alfred Pfeiffer

Thanks, Alfred. I have taken the freedom to translate
Immobilizer into 'Ruhigsteller' for my project on
germanising ABChess, but this is not yet fixed.

--JKn

Well, it's not exactly on this site, but....
http://www.chessvariants.com/link2.dir/chessplusdeck.html

Hmmm, well I want to use 'Chess Plus' and the link is to 'Chess Plus
Dvorak.'  Not exactly the same, so I think I can still call --- Dibs! 
Seriously, though, the linked site is interesting and might make a fun
game for people who don't mind the element of chance in their chess.

If the goal is to avoid confusion, then you should be aware that 
Chess Plus is the name of an existing commercial four-player variant.
The author sells it at

http://www3.sympatico.ca/thejohnston/chess_plus.htm

If you're not concerned about avoiding confusion, then why bother with
calling dibs or anysuch?  Just look at how many superchesses there are.