Othello

Othello is a strategy board game played between 2 players. One player plays black and the other white.

Each player gets 32 discs and black always starts the game.
Then the game alternates between white and black until:

one player can not make a valid move to outflank the opponent.
both players have no valid moves.
When a player has no valid moves, he pass his turn and the opponent continues.

A player can not voluntarily forfeit his turn.

When both players can not make a valid move the gane ends.