Three-Check
Check your opponent 3 times to win the game.
The rules
Ordinary chess, plus one extra way to win: check the opponent three times.
The third check ends the game immediately, whatever the position looks like.
Material does not matter — you can be a queen down and still win by checking.
Checkmate wins too, as always. A move that gives double check counts as one
check, not two.
The check count is shown next to each player during the game.
What changes
Every check is worth something, so moves that would be pointless in ordinary
chess become real threats. Sacrificing a piece to land one check is often
correct at 2-2.
Defence changes shape as well. King safety is no longer about avoiding mate; it
is about not being reachable at all.
What to watch for
Count before you trade. At 0-0 a check is a small gain. At 2-2 the same
check ends the game, so the same position can be winning or losing depending
purely on the tally.
Blocking squares matter more than pieces. A pawn on h3 that stops a bishop's
diagonal can be worth more than a rook, and giving it up "for activity" can lose
on the spot.