The Fire Elemental started life as a torch with an attitude. It scorched the hands of five Legionnaires of Doom before being brought up for formal disciplinary charges before the Commandante. The court-martial was brief but contentious, resulting in a sentence of demotion to candle and the loss of three weeks’ pay. The candle was assigned to the dinner table the Legionnaire Officer’s Club, where it sat sullenly amidst the white linen tablecloth, crystal skull goblets filled with dark crimson bloodwine, and elegantly plated Mexican food (it being Taco Tuesday). Nobody’s quite sure what happened next, as there were no survivors from that dinner; but the forensic wizard squad later pointed out that tacos are extremely flammable, as is flatulence, and that they certainly wouldn’t have placed a candle with a grudge in such an incendiary dining setting.
The enormous flaming humanoid figure which stalked out of the smoldering remains of the Officer’s Club was immediately given an officer's commission, since - by definition - anyone in the Officer's Club must be an officer. The creature still has an attitude. However, as long as it is given plenty of enemy troops to burn, it generally follows orders. It is worth noting nonetheless that the Legion of Doom has quietly discontinued Taco Tuesday and replaced it with Wasabi Wednesday, sushi being less flammable.