Backlash

Backlash is played on two boards with two full Chess sets. Each turn, players make a move on each board. Captured pieces can be re-introduced by drops as in Shogi. But, unlike other games with drops, captured pieces do not change sides! The player who has a piece captured gets to keep it and drop it - but only on the other board. This makes capturing your opponent's pieces a double-edged sword... weakening your opponent on one board makes him stronger on the other board. Each time a piece is captured, however, it is demoted one level, as in Mortal Chessgi. A captured Pawn is removed from the game completely.

Setup

The game is played on two boards. The left-hand board (from White's perspective) has the usual rank and file notations. The right-hand board has files labeled with capital letters to distinguish it. Additionally, each player has one "pocket" square for each board. White has pocket squares p1 and P1 and Black has pocket squares p8 and P8.

Rules

Turn order

Each turn, players make two moves – first on the left board then on the right board (from that player's point of view.) EXCEPTION: On the first move of the game, White only makes one move, and that move is on the right-hand board. This balances out the first-move advantage. Each player has the first-move advantage on one of the two boards.

Drops

Any pawn that is captured is removed from the game forever. Pawns are never recycled.

Any other piece that is captured is demoted one level and moved to the player's corresponding pocket square for the other board. For example, if White captures a Black Rook on his left-hand board (the one with the lower-case files), a Black Bishop is placed on P8 (Black's pocket square for the other board, the one with the upper-case files.) If a piece was already present on that pocket square the piece that was there is lost and removed from the game. This makes it risky to hold pieces in the pockets rather than dropping them.

Captured pieces are demoted one level as follows:

Queen > Rook > Bishop > Knight > Pawn

Instead of making a normal move on a board, a player with a piece in the corresponding pocket square for that board may instead drop that piece on any open square. The only restriction is that Pawns may not be dropped on the first or last rank. A Pawn placed on the second rank can make a double-space move (subject to En Passant capture as usual.) Any Rook dropped is always considered to have moved and is not eligible to castle.

Victory Condition

The game is won by capturing the opponent's King on either board. The first King to fall ends the game. There is no check, checkmate, or stalemate.