Fire Gobblegut is a fiery version of Gobblegut, from Bowser Jr.'s Fiery Flotilla. He is a secret boss hidden in the Battle Belt Galaxy, in Super Mario Galaxy 2, and is fought in the mission Snacktime for Gobblegut.
Fire Gobblegut has several changes to his body from his normal form. First, his skin color changes from a spring green to a lava red. Not only that, but also his body radiates lava, burning Mario at the touch.
The powered-up Gobblegut is fought in the same manner as Gobblegut. This time however, whenever he bites on the planet, a pool of lava appears. When only a handful of Bellyache Bulges remain, Gobblegut begins to spit out fireballs at Mario, creating pools of lava where they land.
Bellyache Bulges are found at various intervals along the serpentine body of Fire Gobblegut when he is fought in the Battle Belt Galaxy. They appear to be large pink inflamed ulcers, six of which appear along Fire Gobblegut's body. When Fire Gobblegut burrows into the ground, the Bellyache Bulges will become stuck in the ground, at which point the player must attempt to spin each of the six Bellyache Bulges, popping them and causing them to disappear. Mario can also perform a backflip and then spin to hit the Bellyache Bulges when they are above him. Each time one is destroyed, 10 Star Bits are released, and Fire Gobblegut takes more damage. In effect, these Bellyache Bulges act as Fire Gobblegut's only weakness because he cannot be damaged by any other means aside from this. When all six of Fire Gobblegut's Bellyache Bulges are destroyed, he explodes and the Mario wins the battle.
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