Chack'n, a small yellow creature with extendable legs must traverse a series of single-screen mazes. He is capable of walking on floors or ceilings but not walls. He can climb steps and traverse high walls by extending his legs until he is tall enough to pass onto the next step. He is capable of throwing hand grenades to his left or right which, after a short period, explode into a cloud of smoke. Separate fire buttons control rolling to the left or right. Chack'n is killed if caught by the explosion cloud.