Squirm is a Snake-type game which finds you, the player, prospecting for diamonds, to your consternation, the precious stones are guarded by packs of rampaging ghosts. These supernatural spooks - for their own ghostly reasons - line up in tight, orderly ranks that march horizontally across the screen. Your task is to squirm past the ghosts and grab the solitary, blinking diamonds without getting caught.

Unlike most Snake variants, you're free to touch the walls, reverse course, or travel through your own tail without penalty. When you (or the ghosts!) snatch a diamond, a new one will appear elsewhere, if you're the lucky catcher, you gain 100 points and a longer body. You only get a single life to accumulate as much loot as you can: one touch from a ghost, and your hoarding is over.