Set all enemy vessels and rocks at any place on the game board. Place the torpedo boats in the port corresponding to their colour. First player spins the spinner and moves his/her boat in the direction indicated. If a torpedo boat moves onto a space occupied by an enemy vessel, that player takes the vessel off the game board and scores the points indicated. If the boat hits a rock, it is moved to the nearest port for repairs and the player misses two turns. If a boat lands on a space occupied by another player's boat, or if the boat travels off the game board, the moving player stays on the original spot and loses one turn. The game is over when all enemy vessels are sunk, or when the play time has elapsed. The winner is the player with the highest score. —description from the rulebook