Tapatan is the Philippine version of the three-men’s-morris family played from Ancient Rome to China. Unlike noughts and crosses the game does not end when the pieces run out: players then slide their stones along the lines hunting for the winning row.
Variant implemented
Classic Tapatan: 3×3 points with diagonals, 3 pieces each, drop phase then slide-to-adjacent phase, win by making a line of three.
Board and pieces
Nine points in a 3×3 grid, joined orthogonally and diagonally.
Setup
Three pieces each, all in hand.
Turn
Players alternate placing a piece on any empty point. Once all six are down, a turn is moving one of your pieces one step along a line to an adjacent empty point.
Capture and scoring
None — no piece is ever removed.
Win condition
Make a line of three of your own pieces, orthogonally or diagonally.
Draw condition
Threefold repetition or a long stretch with no progress is a draw.
Special rules
The centre is strong but not winning. Unlike noughts and crosses the game does not end when the pieces run out, which is what gives it depth.
Computer opponent
Alpha-beta. The game is small enough that Hard plays perfectly.