Spirax is played on a board of concentric circles. The circles have paths connecting them which spiral inwards towards the central vortex. Each player has four pieces which start along one spiral. Each turn the pieces can be moved by allocating movement points, with movement becoming more expensive the closer a piece is to the vortex. In addition, on some turns every piece on the board will move one space closer to the vortex. Pieces can attack others by moving over them. The result of a successful attack is to send the defending piece in towards the vortex. Pieces which enter the vortex re-appear along the edge. The object of the game is to make a certain number of successful attacks.