Fire Chomp

Fire Chomps are enemies that resemble Chain Chomps, but differ in several ways. First, they are not restricted by chains, instead floating along with a tail made of fire. At any time, they may shoot fireballs at Mario or Luigi. The fireballs are taken directly out of their four-fireball tail. When it run out of fireball, the Fire Chomp will explode, damaging the Mario brother if he's within the blast radius. They live mainly in the skies.

Super Mario Bros. 3
In Super Mario Bros. 3, Fire Chomps only appear in Worlds 5 and 6. They float along as Mario and Luigi navigate the stage, harrying Mario's progress on the small platforms, especially in World 5-9, where the player has a limited amount of platforms he can jump onto in addition to an automatically-scrolling screen. They can be defeated with stomps, fireballs, hammers, Starmen, and tail whacks.

Super Mario 64 DS
In the remake, Super Mario 64 DS, Fire Chomps replace Kuromames. They remain motionless and have the same effect as them, shooting a flame at Mario when he approaches, and they can be eaten by Yoshi.

New Super Mario Bros.
Fire Chomps return in New Super Mario Bros., again with a four fireball limit. They only appeared in World 7-1. They can be defeated by just jumping on their heads. Unlike Chain Chomps, which are almost invincible (bar a few techniques and powers of special characters), Fire Chomps can safely be jumped upon. Doing so knocks them out of the sky. Once they run out of fireballs, they explode like Bob-ombs.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, Fire Chomps are a bit more common, appearing in World 2-6, World 8-3, and World 9-6. Fire Chomps have the same attack pattern as in the previous game but have now developed a new attack in New Super Mario Bros. Wii. When this enemy runs out of fire, it flashes red and self-destruct seconds later, but not before chasing Mario much faster than it was originally doing. They can be defeated with a single jump like in the previous game, but oddly enough, they can be defeated with fireballs.

The Adventures of Super Mario Bros. 3
Fire Chomps made several appearances in The Adventures of Super Mario Bros. 3, such as in the episode "The Beauty of Kootie", where several Fire Chomps act as crew members on Bowser's Doomship.

Nintendo Adventure Books
A Fire Chomp appears in Koopa Capers, prowling a cave in the Magma Pits. While Luigi is fleeing from the Hot Feet that also live in the cave, he can choose to either rush blindly ahead, or take his time; if he chooses the latter, he will just narrowly avoid the Fire Chomp, but if he picks the former, he will run into and be scorched by the fireballs of the Fire Chomp, causing a Game Over.