XYMYX was created in Ecuador 6 years ago
and its main idea is simultaneity, that is, players make their moves at the
In xymyx both players make their moves simultaneously and because
of this whoever plays with the white pieces has no advantage, colors
practically don't exist. Because of all the knowledge involved in chess,
whoever has more experience will have the advantage, but someone who has
learned to play xymyx can easily beat an expert chess player because everything
The starting position of orthodox chess.
Same as in orthodox chess. Colors don't exist. There are no white
or black pieces. Only of a different color.
All the rules are the same as in orthodox chess, except the
To play XYMYX, you only need to know the general rules of Chess and
the 4 rules of XYMYX
The players start the game "simultaneously"
(ie. the players make their moves at the same time).
pieces to the same empty square
Because of the simultaneity, two pieces can end up in
the same empty square:
a) If the pieces
have different hierarchy, the one with higher hierarchy will stay.
b) If the pieces
have the same hierarchy, the piece of the player who first records the move
Self-capture your own pieces.
In XYMYX you are allowed to capture your own pieces.
When with a simultaneous move the pieces of both opponents move to
an occupied square, the piece of the player who initially was in the square
will stay, maintaining the piece that was moved in the simultaneous play. In
this kind of move hierarchy will not govern.
a player is checked by the queen, the queen cannot be moved in the following
move. The player must move any other piece.
The following notes are not rules but clarifications for some
moves that could be confusing.
The Check must be counteracted
-inevitably on the next move-
by moving the King to a square where it is not in Check..
You MUST NOT:
a) Capture the piece
which is checking your King
b) Move one of your own
pieces between your King and the checking piece
There are no Pinned Pieces.
You can move your pieces even if they are protecting your King.
Why? The King will be in check only in the next move.
a result of the simultaneous move, it is possible that with a move one piece
tries to capture another, and at the same time the target piece moves to
another square. In this case, no capture will exist. It is important to mention
that this rule affects the Pawns as well, which can only capture in cross squares
The following are
uncommon and unusual moves:
It is possible that two Checks happen at the same time.
Check vs. Check. Both players must move their Kings.
Mate vs. Check. The game ends and the winner is the player who has
checkmated the opponent
Mate vs. Mate. The player who registers first the move of the Mate
King vs. Pawn
The King could move to f3 because the Pawn only forbids the move
to e3 (this square is attacked by the Pawn)
If the Pawn of f4 and the King of e4 moves at the same time to f3,
the King will stay and the Pawn will be captured (Rule 2. two pieces to the
same empty square)
When the Pawn reaches the eighth rank, it shall be immediately
exchanged with a piece of the Pawn's color as a part of the same move,
independently from the pieces which remain in the chessboard.
The "bottom" player wins by check mate.