Puffy Wario

Puffy Wario is one of Wario's many transformations in the Wario Land series of games. To achieve this transformation, Wario must be stung by a bee enemy, like a Beezley from Wario Land 4. He will then swell up, filling his head with air, allowing him to slowly float upward until he hits the ceiling. He would then return to normal, and fall back down.

Some of Catbat's minions could turn Wario into Puffy Wario.

Trivia

 * Part of this reaction on Wario could be the result of a, possible, lethal allergy Wario has on bees.