The Zapper, Pusher and Grabber robots were dropped onto the planet of the Shinerians, but are now desperate to return home. They have killed off the Shinerian race, but must climb a high tower, negotiating all the traps it holds, before they can contact their masters.
Each robot's name indicates what their main function and purpose is, and these skills must be combined for success. Each section has its own task - collecting energy pods and destroying mines and bombs for example. The creatures which fill the towers must be avoided, or used to your advantage.