Super Methane Bros

This platform game bears a similarity to Bubble Bobble in many ways. There are 100 single-screen levels, featuring variously shaped ledges, for the two characters to face before escaping from the Tower of Time.

These levels are laden with nasty bugs, but you have a methane gun to shoot at them. This absorbs them, and allows them to be fired out against a wall; if they don’t reach the wall, they live to fight another day. You must destroy them all within a specific time limit to progress.