Jörg Knappen wrote on Tue, Oct 16, 2012 06:30 AM EDT:
Hmm... it your decision, at last.
Possibilities include:
(1)
If you cannot gate in a piece in the last possible move because you are in check, this counts as checkmate and you lose the game.
If you cannot gate in a piece in the last possible move and you are not in check (may happen on a very crowded board), this counts as stalemate and the game ends in a draw.
(2)
Game goes on and you just have forfeited the right to bring that particular piece in play (put it to the place where the captured pieces are). For most pieces this is a huge penalty, but you may even want to trigger this situation in order to avoid a Wuss on your side.
Maybe additional rules become necessary: What happens if you can gate in either a pawn or a major piece, but not both (e.g., because you can block a check with a pawn move or a piece move)?