Calorite

Calorites are firey monsters holding two small logs found inside the Flab Zone of Bowser's body in Mario & Luigi: Bowser's Inside Story They will use the two logs in their hands to increase the power of their flames and then the Calorite will begin rolling while shooting flames at both bros. This attack can be avoided if the heroes simply jump over the flames. If Mario or Luigi are hit by this attack, they might get a burn, making them lose a few turns and not be able to counterattack. It will also eat Tenderlings to turn them into another Calorite.

Trivia

 * The Calorite is the only enemy in the game that can inflict the Burn status ailment on Mario and Luigi.