Unibo

Unibō (ウニボー ), from "uni" or "sea urchin", are spiky round enemies that inhabit flying and swimming areas. Unibō are nearly indestructible; in Super Mario Land 2: 6 Golden Coins, they can be defeated by only a Star or Koopa Shell. They remain stationary until Mario comes near, at which point they will shake on the spot to make themselves harder to avoid. They reappear in Mario & Wario, slightly redesigned to look more like Urchins and their visible eyes removed (although they could be facing away from the screen). In addition, they now come in two varieties: those with blue bodies move vertically, and those with yellow bodies move horizontally. In addition, they no longer sleep and are contantly moving around.

The original appearance of Unibō is very similar to both Gordo from the Kirby series and Sea Urchins from the Zelda series.