The rules of Nomic Chess start out like regular chess, except that when it is your turn, instead of making a move, you can change the rules such that any particular class of pieces (say pawns) can move like any other class of pieces (say queens).
An optional second rule is that when you are in check, you must make a move, not a rule change, in order to get out of check. (Otherwise it can be extremely difficult to arrive at a checkmate if any attacking piece can be turned into one that moves like a pawn or whatever).
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Nice idea. But I have a question.
If in the course of the game a player says “from now on, pawns can move like queens”, and later in the game a player says “from now on, bishops move like pawns”, does the second move mean that bishops move like pawns in the standard game? or like pawns at this point in this game (i.e. like queens in the standard game)? Late-binding or early binding? Interpreted or compiled?