Backplay chess - Chess Forums

lucrus

Aug 1, 2021

0

#1

Let's start with a checkmate position, or a resigned position, a drawn position or a random position you like. It doesn't matter which one you choose, as far as it's not the starting position and it's at least a middle-game position, better if end-game. You can take a famous game as well as a puzzle from a magazine.

The target for each player is playing valid moves backwards, in order to reach the starting position of his/her pieces faster than the opponent. The first one that reaches the starting position wins.

Let's take this one for example:

Here white has won, so the last move was played by white. White makes the first "backplay" move.

Now black must make next "backplay" move, but, before that, he/she has a chance to decide if the move white played was a capture move or not. For example black can decide that the last move by white was a capture move and that there was a queen in the e8 square before the rook captured it and chekmated the black king. So, before moving, black puts a queen back in the e8 square:

Now black makes the next "backplay" move, and chooses bxa2, forcing white to place a piece or a pawn in a2, because otherwise the black pawn could not have moved that way:

White can choose any piece for the a2 square, including a light-squares bishop, but, doing so will make his/her life harder, because reaching the starting position from there would then include going through a pawn promotion to a light-squares bishop in the following (er... preceeding) moves, otherwise there's no way two light-squares white bishops can coexist. But let alone that corner case, let's assume white puts a rook in a2 and "backplays" d4 from d2:

Now black chooses to "backplay" kd8 form the c7 square, so he/she puts the king on c7:

This forces white to choose one between the only possible moves that led to that position, e.g. cxd6+, d6+ or exd6+, because otherwise there's no way for the king to be under check. White chooses cxd6+ and forces black to place something on d6, and so on.

General rules:

1. Start from a endgame postiion

2. Play the game backwards, trying to guess what moves could have led to that position

3. reach the starting position before your opponent to win the game (assuming you and your opponent chose a real endgame and you both backplay only the real game moves that were played, obviously black will always win, but it's easy for white to avoid this by diverging from the real game moves on his/her first backmoves).

4. After you put something back on the board and after you "backplay" a move, the board must be in a valid and legal position, e.g. no two kings of the same color, no more than 8 pawns per color, no checkmate positions allowed, if you already have 8 pawns no martian pieces allowed (e.g. two light-square bishops, three rooks and so on, because with 8 pawns no promotion is possibile in the following backplay moves) and your opponent must have at least one legal move to backplay. When you realize you're not respecting this rule, you must choose something else to backmove or to put back on the board (or don't put anything at all back on the board, if allowed). If you are forced to put something on the board , but anything you choose breaks this rule, that means your opponent must undo his/her last "backplay" move. The only exception to this rule is when you reach your starting position while you are playing white (because white moves first in real chess, so we must allow white to break this rule to let white win before black reaches his/her starting position).

What do you think of this variant?

lucrus

Aug 1, 2021

0

#2

Also, we can play "backplay chess 960" where you win as soon as you reach anyone of the Chess960 starting positions. I guess it would be easier and faster variant of this variant.

Sharkboy2021

Feb 18, 2022

0

#3

Epic