A horizontal scrolling shoot 'em up. Control Captain Beeble through a series of tunnels and caves by directing the thrust of his jet-pack, similar to the control in Asteroids. A light gravity effect is the only external force moving Captain Beeble. Exterminate enemy bugs while moving blocks to retrieve a crystal and return it to the Crystal Processing Unit. Beeble's task is complicated by limited jet-pack fuel and the volatility of the crystal. If he carries the crystal too long it explodes. Levels get progressively harder with the introduction of more obstacles, narrower tunnels, more bugs, and poisonous walls that cause Beeble to explode on contact. Converted from the Atari XL.