Ruff 'N' Tumble

Ruff Rogers has lost his marbles - in the literal sense of the small round balls used to play a game on drains. He's been armed with a gun to retrieve them from 16 levels of side-scrolling platform shooting.

The gun you start with isn't especially powerful, but various machine guns and flamethrowers can be collected, which make much lighter work of the enemies. Your character can jump and duck responsively, and fire at all angles.