The Chess Variant Pages

Cheapmate Chess

A humble variant

Invented by Robert Price

I got the idea for this variant while I was reading the FIDE Handbook for the first time. Most chess variants are made by adding some additional rules, or modifying existing ones. This variant results from the deletion of a rule, or at least part of one.

To quote article 5.1.a of the FIDE Handbook effective July 1, 1997:

The italicized portion is necessary because, ordinarily, an illegal move is allowed to stand if its illegality is not noticed before the end of the game, so an illegal move resulting in checkmate would otherwise not have a chance to be declared illegal.

In Cheapmate Chess, all FIDE Chess rules apply except for that italicized section. Thus it is possible to achieve checkmate by means of an illegal move. I call this situation cheapmate.

Now, I don't want to allow the movement of multiple pieces, or the reintroduction of pieces that have already been captured, so here are the rules governing the FIDE-illegal move:

If the FIDE-illegal move results in checkmate or stalemate, then the game is over. Otherwise, the opponent may declare that the move was illegal, and, according to the rules of FIDE Chess, the position is reset to just before the offending move, and the player who made the move makes another. Attempting to play an illegal move is not, in itself, grounds for a penalty or loss of game.

There is a Zillions of Games implementation of this game (should appear below in the "see also"), but it runs into "Too many moves were generated" trouble when you try to make the computer play. Also, it lets you play an illegal move at any time, but if the enemy can evade check, you lose.


Written by Robert Price
WWW page created: May 24th, 2002.