Petey Piranha (Final Smash)
When this Final Smash is used, Piranha Plant summons Petey Piranha. He jumps around capturing opponents in the cages he holds while the player has free control of Piranha Plant. Petey will move in the same direction Piranha Plant is facing, regardless of whether it is moving or not, and will jump in tandem with it. After a few seconds, he will enter his attack phase and stop following the player. He will breathe fire on both cages, slam them onto the ground, launching any opponents trapped in them, and fly away. Petey Piranha can fall off of ledges, though players in the cages will be propelled upward, usually to safety, before they hit the blast zone. He will also leave burning flames on the ground at the end of the Final Smash left from the fire-breathing.
Petey Piranha first appeared in Super Mario Sunshine and has appeared - usually as a boss, but many times as a playable character - in various Mario titles since. His cages are based on his appearance as a boss in Brawl's Subspace Emissary, where he captured Peach and Zelda in said cages and flung them around, similarly to how he flings them down during the Final Smash. This is the first time he is shown able to breathe fire, as he usually spits out poisonous toxins and goop in the Mario series.