Chess AI for Mac

Overview of the game

Chess AI is an open-source single-player chess title created by Sebastian Lague. It follows the same standard chess rules as other online chess programs and lets you face off against a computer opponent across adjustable difficulty levels. The primary objective is to force the opponent’s king into checkmate using the conventional rules of chess.

Starting position and pieces

The board is an 8×8 grid of alternating light and dark squares, giving 64 squares in total. At the beginning of a match there are 32 pieces in play — 16 for each side. The set for each player includes:

• 8 pawns
• 2 rooks
• 2 knights
• 2 bishops
• 1 queen
• 1 king

Pieces are deployed in the standard opening formation on the two nearest ranks to each player.

How the pieces move

Each piece has its own legal moves and captures; players must always make a legal move on their turn (skipping is not allowed). Key movement rules:

• Knight: moves in an L-shape (two squares in one direction and one perpendicular) and can jump over other pieces.
• Pawn: typically moves forward one square; from its starting rank it may move two squares. It captures diagonally, can perform en passant in specific situations, and promotes upon reaching the far rank.
• Rook: moves any number of empty squares along files (vertical) or ranks (horizontal).
• Bishop: travels diagonally any number of vacant squares.
• Queen: combines the rook and bishop, moving any number of squares vertically, horizontally, or diagonally.
• King: moves one square in any direction and must be protected from check; special castling rules allow a two-square king move with a rook under certain conditions.

Capturing removes the opponent’s piece from the board by occupying its square.

Objective and game outcomes

The match is won by checkmating the opponent’s king — that is, placing the king under attack with no legal move to escape capture. Other possible results include stalemate (a draw when the player to move has no legal moves but is not in check) and various types of draws by agreement, repetition, or insufficient mating material.

Playing against the AI

Sebastian Lague’s Chess AI is well suited for players learning piece mechanics and basic tactics. While it may not fully replicate the unpredictability of human opponents, it provides multiple difficulty settings and consistent practice for opening ideas, tactics, and endgames.

Other options

If you want alternatives, there are many chess programs and puzzle games available. For a different casual title, Purble Place is an example of a paid, non-chess option that focuses on mini-games and pattern recognition.