Standard chess, with one twist. Pick a variant, pick a color, and play against a simple bot.
SpecialChess is standard chess with one rule changed, built as a way to explore how a single tweak can reshape strategy without touching the rest of the game. Both variants keep the standard board and the normal rules for how pieces move, check, checkmate, stalemate, castling, en passant and promotion — only one mechanic is different.
Every move is on trial for one round. Right after you make your next move, your previous move snaps back to where it started — if it legally can. The return only happens if the piece is still on the square it moved to, the path back is clear, and stepping back wouldn't leave your king in check. Otherwise the move sticks for good.
That makes quiet moves a real choice. Move a bishop out, and on your next turn you can block its way home with another piece to lock it in place — or let it snap back and spend the tempo elsewhere. Pawns can't move backwards, so pawn moves always stick. Captures are one-way: the capturing piece may return, but the captured piece stays off the board. Castling, promotion and en passant are never undone.
Each turn is two moves in a row instead of one. Both moves must be legal on their own, and neither may leave your own king in check. Your first move can give check without ending your turn — you still make your second, and your opponent starts their turn in check. If your first move is checkmate, the game ends there. With two moves a turn, attacks that normally take several turns to set up can land at once, so calculation matters even more than in normal chess.
You play against a simple bot that runs entirely in your browser. Pick a variant and a color to start; there's no login, and no game is saved on a server or linked to you.
Yes, the basics. Everything except the one new rule works exactly as in standard chess, and the rules panel during a game recaps the variant.
It's a simple bot, good for learning how the variants feel rather than a serious challenge for strong players.