Hermit crabs have a shell on them, which is brownish coloured. Visible in the shell are two glowing yellow eyes. Attached to the bottom of the shell are two crab arms, and below the arms are two legs on each side.
Hermit crabs are found in levels walking on walls, floors, and ceilings. They have no attack and cannot walk on to an adjacent platform. In some cases, they can walk on dry land, depending on their path.
The submarine can roll past hermit crabs on dry land to sustain damage if they want to complete the level more quickly. Hermit crabs can be killed with three bombs, and yield an emerald upon death.