In Mad Elephant Chess a player may as their move convert a Pawn into an Elephant (also known as an Alfil, which means "The Elephant" in Arabic). Elephants in turn, may upon reaching the back two rows promote to Mad Elephants, which can rampage, capturing all the pieces in a line in front of it. The object of the game is the capture, not checkmate of the King, and Pawns can taunt their opponent's Mad Elephants, causing them to trample the taunting Pawn (and even to trample either side's King!). Elephants and Mad Elephants replace the Bishops.
The rules of Mad Elephant Chess are identical to those of orthodox chess, except when noted below. The largest general rules change is that the object of the game is to capture the opposing King, not to checkmate it. This means among other things that the King may be moved to a square on which it may be attacked. If a single move causes both your King and your opponent's King to be captured, the game is a draw (this can happen as the result of taunting a Mad Elephant to rampage on a line that captures both Kings). The standard board and array are used, except that Queen-side Bishops are replaced by Mad Elephants, and King-side Bishops by Elephants.
Pawns have all of the usual powers of usual orthodox chess Pawns. In addition they have two special moves: they can change into Elephants, and they can taunt Mad Elephants (Nyah-nyah-nyah-nyah-nyah!).
Changing into an Elephant counts as the player's move for that turn; the Pawn is removed and the Elephant is placed on the same square.
In order to taunt, a Pawn must start the turn adjacent (in any direction) to one or more of their opponent's Mad Elephants. The player's move consists of announcing that the Pawn is taunting their opponent's Mad Elephants (the Pawn does not actually move). If there is more than one of the opponent's Mad Elephants next to the Pawn, they all are taunted -- the moving player does not get to choose. On the opponent's next turn, one of the taunted Mad Elephants must rampage in such a way as to trample the taunting Pawn; see Mad Elephants below for details. You may not taunt one of your own Mad Elephants (it wouldn't be nice), and any of your Mad Elephants next to a Pawn of yours taunting the opponent's Mad Elephants are not affected.
Pawns promote normally upon reaching their opponent's end of the board. They may promote to an Elephant, Mad Elephant, Knight, Bishop, Rook or Queen.
Elephants move like Alfils, a jump of two squares in any direction, leaping over any pieces that may occupy the first square. Like so:
An Elephant is a weak piece that can only reach 1/8 of the squares on the board, often no stronger than a Pawn.
Elephants promote to Mad Elephants upon reaching their opponent's 7th or 8th rank. This is a mandatory promotion like a Pawn promotion -- there is no choice.
Mad Elephants can move just like regular Elephants. In addition, they can also (and sometimes must) make a special move called a rampage. When a Mad Elephant rampages, it moves in a straight line on any Queen-line until it reaches the board edge, trampling (capturing) all pieces of either side it encounters.
For example: in the following diagram white's Mad Elephant is marked in yellow and black's Mad Elephant in red; it is white's move.
In addition to jumping to c1 or to c5, white's Mad Elephant (on a3) could rampage M:a7:a8, M:e7:f8, Mh3 or M:b2-c1 (see below for an explanation of the notation).
Mad Elephants however will not rampage toward a King of either side, unless they have been taunted. (They know they're not supposed to trample their King, so they won't rampage toward either King, just to be on the safe side; however, if they've been taunted, they get so mad that they forget that.) It is legal to rampage without trampling anyone. Mad Elephants may capture Kings by their normal jumping move.
If any Mad Elephants were taunted on the previous move, the player owning them must move one of the taunted Mad Elephants such that it rampages over the taunting Pawn. This move take priority over any other move. In the above diagram, the rampage M:a7:a8 could be followed by b7(T), which would then be forced to be followed by M:b7:c6:g2:h1. If the Pawn taunted more than one Mad Elephant, it is the moving player's choice which one rampages. Any others are not forced to rampage -- they're satisfied when their compatriot tramples that impudent Pawn flatter than a pancake. A taunted Mad Elephant may tample either side's King (or both!).
Mad Elephant Chess uses standard algebraic Chess notation with a few additions. Elephants are are E and Mad Elephants are M. A taunting pawn is indicated by location and (T), so b2(T). A rampage is listed as a series of captures, with possibly a noncapturing move at the end to indicate where it ended up; for example: M:a2:a5:a6-a8 (or Mxa2xa5xa6-a8 if you prefer).
No Starting Elephants
In this subvariant, the bishops remain in place as usual. The only Elephants and Mad Elephants in the game are those resulting from promotion and Pawn conversion.
Everyone can Taunt
In this subvariant, all pieces can have the dubious pleasure of taunting Mad Elephants, not just Pawns.
Mad Elephant Chessgi
A blend of Mad Elephant Chess and Chessgi. The only unobvious part is that pieces trampled by Mad Elephants would not go into hand -- instead, they are removed from the game. They're too flat to play any longer.
The original inspiration for this game was an observation by Pritchard that in Shatranj an Alfil/Elephant was worth no more than a central Pawn. Well, if they aren't worth more than a Pawn, why not allow them to be substituted for Pawns? The problem with that was that by themselves, Elephants aren't that interesting. But what if they could run amok? This game is the answer to that.
Originally, the King-side Bishop was also replaced by a Mad-Elephant, but that was too advantageous for white: 1. Md3 ..., 2. M:d2:h7 R:h7, 4. M:d7:d8 ... Not good. The current set up is a compromise between wanting to have Mad Elephants on the board at the start when they're the most fun, and trying to balance the starting positions.
Elephants are obviously very weak, but how strong is a Mad Elephant? Unlike an Elephant, a Mad Elephant can visit every square on the board. The diagram of how many moves it takes to reach a particular square is kind of interesting:
+---+---+---+---+---+---+---+---+ 8 | 2 |:2:| 3 |:1:| 2 |:2:| 2 |:1:| +---+---+---+---+---+---+---+---+ 7 |:1:| 4 |:3:| 4 |:3:| 3 |:4:| 2 | +---+---+---+---+---+---+---+---+ 6 | 2 |:1:| 2 |:3:| 3 |:1:| 3 |:2:| +---+---+---+---+---+---+---+---+ 5 |:2:| 4 |:2:| 3 |:3:| 3 |:3:| 2 | +---+---+---+---+---+---+---+---+ 4 | 1 |:4:| 3 |:M:| 3 |:3:| 4 |:1:| +---+---+---+---+---+---+---+---+ 3 |:2:| 2 |:2:| 3 |:2:| 2 |:3:| 3 | +---+---+---+---+---+---+---+---+ 2 | 2 |:1:| 2 |:4:| 4 |:1:| 4 |:2:| +---+---+---+---+---+---+---+---+ 1 |:1:| 2 |:2:| 1 |:2:| 2 |:1:| 2 | +---+---+---+---+---+---+---+---+ a b c d e f g h
It can reach any other square from a center square in four moves, but exact number of moves to each any particular square may not be obvious. However, how strong is it? The rampage attack is very powerful, particularly early in the game when there are a lot of pieces. However, in the endgame, the restriction on rampaging through Kings can make it a fairly weak piece. My unscientific opinion is that is starts off being worth a little less than a Rook, but by the endgame it is worth a Knight or less.
While not a Chess problem composer myself, it seems to me that some amusing problems could be composed using this variant.