Helio (Wario Land 3)

Helio is a character that appeared in Dr. Mario 64. He patrols the sky, watching for ongoers. In the story, he is angered by Dr. Mario/Wario while they chase Mad Scienstein to get the Megavitamins. Because of this, he pokes Wario/Dr. Mario and the next character to cross him has to play him in a match.

Traits
Helio looks like a balloon with arrowheads on his arms. Apparently, there is a toxin that turns Wario into Balloon Wario on the tips of the arrowheads. Helio is easily frustrated, as portrayed in the game.

Trivia

 * There is an enemy in Super Mario RPG Legend of the Seven Stars also named Helio.