The fish will inflate whenever it is struck by Bob-ombs, leaving it vulnerable to attack from Mario's pinball form. It will primarily swim calmly around its lair, but after a certain amount of time has gone by, the fish will extend its spikes and directly home in on Mario to knock him out of the room. For each hit it takes, the fish will summon two Spiny Cheep-Cheeps to aid him in his attacks (or just one if one has already been defeated). These enemies can be defeated by using the pinball flippers to toss a single Bob-omb at them.
- In Japanese, its name is ボストゲプク, which translates to Bosu Togepuku, meaning "Boss Spiny Cheep".
- In Spanish, its name is "Porcu-Puffer Jefe", which means "Porcupuffer Boss".