Chess
Classic chess against the computer with the complete rulebook: castling, en passant, promotion, checkmate, stalemate, the 50-move rule and threefold repetition. Three levels of alpha-beta minimax AI, legal-move hints, undo, and mid-game save to continue later. Win fast and keep more material for a higher score.
Chess needs little introduction, and this version plays by the complete rulebook — castling, en passant, promotion, checkmate, stalemate, the fifty-move rule, and threefold repetition are all handled. You face an alpha-beta minimax engine across three difficulty levels, with legal-move hints, undo, and mid-game saving so a long battle can wait for you. Winning quickly while keeping your material scores highest.
How to play
Tap one of your pieces to reveal its legal moves, then tap a target square to move. When a pawn reaches the last rank you choose its promotion piece — Queen, Rook, Bishop, or Knight. Keyboard play is supported too: arrow keys move the cursor, Enter or Space selects, U undoes a move pair, and N starts a new game. Only games you win count toward the leaderboard.
Tips
- Control the center and develop your knights and bishops early rather than pushing many pawns.
- Castle early to tuck your king into safety — winning a castled game also unlocks an achievement.
- On Hard the AI searches four plies deep with quiescence, so avoid hanging pieces to cheap tactics.
- When your king square glows red you are in check, and only moves that escape it are allowed.
For more thinking games, try Checkers or Gomoku.
Objective
Checkmate the computer's king. Only WON games count on the leaderboard — win quickly and keep more material for a higher score.
Controls
- Tap/click one of your pieces to see its legal moves, tap a target square to move
- Pawn on the last rank: pick the promotion piece (Queen/Rook/Bishop/Knight)
- Keyboard: arrow keys move the cursor, Enter/Space selects, U undoes, N starts a new game
- ↶ Undo takes back one move pair, New Game lets you pick White/Black again
Tips
- Control the center and develop knights and bishops early
- Castle early to keep your king safe — winning a game with castling also unlocks an achievement
- On Hard the AI searches 4 plies deep with quiescence — don't hang your pieces
- When in check your king square glows red — only moves that escape check are allowed