Petey Piranha is an abnormally large mutant Piranha Plant with a ring of petals on his head. His first appearance is in Super Mario Sunshine, and since then has become a common, recurring boss in Mario titles, despite seemingly being destroyed after each encounter. He also consistently appears in sports games and spin-offs, and even featured as a playable character in several sports games. Petey Piranha was thought to be a loyal follower of Bowser, but this was undetermined until Mario & Luigi: Paper Jam showed Bowser directly giving him an order. It is quite likely that he is the ruler of his kind, as suggested by his Japanese name, Boss Pakkun, "Pakkun Flower" being the Japanese name for the Piranha Plant. He has multiple special powers and abilities that set him apart from normal Piranha Plants, including spitting Goop, flying using his leaves, and attacking with vines.
On the cover of Super Mario Galaxy 2 (pictured), a ? Block and a Goomba both appear on Starship Mario, even though neither of these things ever appear on Starship Mario in the actual game. Also, the Warp Pipe has been repositioned, as it now appears higher up on Starship Mario's cap, as opposed to in its left ear.