Petey Piranha is an abnormally large Piranha Plant. His first appearance was in Super Mario Sunshine, and since then he has gained much popularity and has since become a regular boss in Mario titles. He also consistently appears in sports games and spin-offs. Petey Piranha is thought to be a loyal follower of Bowser, but this is undetermined. It is quite possible that he is the ruler of Piranha Plants. He has multiple special powers that set him apart from normal Piranha Plants, including spitting Goop and flying.
Petey made an appearance in the first game of the Mario Baseball series, Mario Superstar Baseball, as a team member of Wario's in Challenge Mode. In this game he was a Power type character, the strongest in the game with a batting stat of 9/10, tied with Bowser. He was also the slowest runner, with a running stat of 1/10, tied with Red Pianta, Yellow Pianta and Bowser. In this game, he had good chemistry with Birdo, Donkey Kong and King Boo, but he had bad chemistry with Princess Daisy, Princess Peach, Noki and Pianta. It is unknown why he had good chemistry with Birdo and Donkey Kong, and why he had bad chemistry with Daisy. He had the ability to Body Check, to save him in tight pinches.
Also, Petey Piranha reappears in Mario Super Sluggers again as a Power Character. However, unlike the previous installment, he was a starter character, although he still retained his ability to Body Check. In Challenge Mode, he appeared in Peach Ice Garden in an empty flower pot. If Princess Peach uses her special ability, Petey Piranha appears. In this game he has compatability with Birdo, King Boo, Blooper, and Wiggler.