From the Super Mario Wiki
Ads keep the MarioWiki independent and free :)
“You fools! Do I have to teach you penalty for removing the spell? You get to come for supper... MY supper!!”
Naval Piranha is a recurring Piranha Plant boss. He started out as a normal Piranha Plant, but was altered by Kamek's magic during the events of Super Mario World 2: Yoshi's Island. He grew to gigantic proportions, with long thorny stalk and two secondary Naval Buds. As his name suggests, Naval Piranha inhabits the water. In battle, he spits out Nipper Plants.
Super Mario World 2: Yoshi's Island/Yoshi's Island: Super Mario Advance 3
Naval Piranha is the boss of World 3 in Super Mario World 2: Yoshi's Island, and reprises the role later in the GBA remake. After being magically enlarged and enhanced, he battles the Blue Yoshi, who throw eggs at his only weak point which is his large and bandaged belly button (with the "X" band-aid). After being hit with enough eggs, Naval Piranha is defeated.
A famous trick, exclusive to only this boss, is that Yoshi can beat him before the fight even starts. If Yoshi stands on the very edge of the ledge Naval Piranha is rooted to (or jump from the water and aim) without triggering the scene, he can simply throw an egg at his "unmodified" form to defeat him in one hit. A surprised Kamek then approaches, shouts "OH, MY!!!" and flies away, thus Yoshi clears World 3.
Yoshi's Island DS
During the introduction to Yoshi's Island DS, Naval Piranha makes an appearance alongside the other castle bosses in the game as the events of Super Mario World 2: Yoshi's Island are recapped.
Yoshi's Woolly World
Naval Piranha reprises the role of a boss in Yoshi's Woolly World, in this case being the boss of World 4. After being enlarged by Kamek's magic, the monstrous plant jumps to a pipe in the background, and calls forth its Naval Buds. Shy Guys will then throw bombs at the foreground; which Yoshi must swallow and spit out at the mutant flower's open mouth, causing its to swallow the bomb and reveal her weak spot: its belly button. Yoshi must ground-pound it to deal damage. Then, the Naval Buds will create a series of attacks that Yoshi must avoid. Repeating the process two more times will end the boss battle.
Similar to Super Mario World 2: Yoshi's Island; Yoshi can throw a Yarn Ball at the sleeping Piranha Plant before triggering Kamek's appearance. This causes a slightly different scene, but Naval Piranha cannot be skipped and must be fought this time in order to progress to World 5.
Naval Piranha reappears in level 4-S, where it chases Yoshi through an auto-scrolling level. Yoshi can throw a Yarn Ball at Naval Piranha to make it disappear temporarily, though this does not stop the auto-scrolling and it reappears after a few seconds. It is unknown whether this is the same Naval Piranha as the one fought in the boss level, as it has red vines as opposed to the boss' green vines. If it is able to gobble up the Yoshi while he is moving through the level, he will be instantly defeated.
Naval Piranha also reappears in the Boss Tent. It is fought the same way; however, it attacks faster making it harder to hit it.
Mario Party Advance
Naval Piranha makes a reappearance in Mario Party Advance. At the Bowser Lab, choosing to see the "scary monster" unveils Naval Piranha. Afterward, Bowser has the player face it in the minigame Koopa Kurl. After winning, the player gets to keep the minigame. The end of game credits say it now lives and thrives in the desert.
Names in other languages