Draughts (or checkers) is played by two opponents, on opposite sides of the gameboard. The players alternate turns. It is against the rules to move one of the opponent's pieces. The player with the light pieces moves first. A move consists of moving a piece diagonally to an adjacent unoccupied square. If the adjacent square contains an opponent piece, it may be captured (and removed from the game) by jumping over it to the unoccupied square immediately beyond it. A piece may move only diagonally into an unoccupied square. Capturing is mandatory in most official rules, although some rule variations make capturing optional when presented. In almost all variants, the player without pieces remaining, or who cannot move due to being blocked, loses the game. When a man reaches the crownhead or kings row (the farthest row forward), it becomes a king, and is marked by placing an additional piece on top of the first man, and acquires additional powers including the ability to move backwards (and capture backwards, in variants in which they cannot already do so). As with non-king men, a king may make successive jumps in a single turn provided that each jump captures an opponent man or king.