Jack O'Goomba

Jack O' Goombas are pumpkin-wearing Goombas found in Super Mario Galaxy and its sequel, Super Mario Galaxy 2.

Super Mario Galaxy
Jack O' Goombas made their debut in Super Mario Galaxy. The only places they can be found are in haunted galaxies, such as Ghostly Galaxy. These pumpkin-wearing Goombas are capable of producing small blue flames in an attempt to burn Mario, yet the ability is lost when their pumpkin is destroyed. To break their jack-o-lantern helmets, Mario must Spin. Ground Pounding them, however, will destroy both the pumpkin helmet and the Goomba in one pound. Once they lose their Pumpkin cover, they are simply a regular Goomba. If the player Ground Pounds a Jack O' Goomba after it just produced a blue flame, Mario will get burned if he touches it. Also, if one tries to jump on one, the pumpkin won't break.

Super Mario Galaxy 2
The Jack O' Goombas later reappear in the sequel, Super Mario Galaxy 2. They have not changed much from the predecessor, still wearing a pumpkin mask, releasing blue flames once in a while. Yet these enemies are not limited to haunted galaxies, being found in such places as the Clockwork Ruins Galaxy.

Trivia

 * Jack O' Goomba is a pun on Jack O' Lantern, which is what they are wearing on their head.
 * When touched by Rainbow Mario, only the pumpkin will break.