How to play Sigma Seven on Mac

The space station Sigma 7 has a problem: all robots have gone havoc. Now the player has to set things right by using the central controls inside the station - but of course it is not that easy. He first have to solve three levels with different gameplay mechanics: The first is a diagonally scrolling shooter which plays very basic: don't getting hit by the mines which come in formations of three. It is best to shoot them, however, because surviving mines may come back from the side, which is deadly. After reaching the station, the game becomes a Pac-Man variant. In a maze-like field the player needs to pick up glowing balls on the floor without being touched by the enemies. But there are two important differences: the player controls a tank, i.e. he can shoot the foes, and he doesn't have to pick up all balls. If he got enough, he can simply use the exit. However, a few balls can't be picked up and the pattern needs to be remembered, During the last mini game the player gets presented with a panel of buttons. He bounces a ball on those buttons to recreate the pattern from before. He needs to look after a force field which follows the ball's movements - touching it results in losing a life. The buttons also flash in different colours and the bouncing only gets registered when the right colour is active. After finishing this level the game loops with faster enemies.