In the game, players take the role of Amagon, a Marine who is trapped on an island after his plane crashed. Inconveniently, his rescue ship is on the other side of the island, hence Amagon is forced to attempt to cross it. Along the way, he encounters a variety of enemies which he can dispose of with his machine gun. Amagon also has the ability to transform in to a larger, stronger version of himself (called "Megagon") similar to the Incredible Hulk. When transformed, Megagon can take multiple hits of damage but doesn't have access to his machine gun. He can fire waves of energy from his chest, but it lessens his hit points.