Pyro: featured in UNCANNY X-MEN
Real name: St. John Allerdyce
First appearance: UNCANNY X-MEN #141
St. John Allerdyce, also known as Pyro, is an Australian mutant with the ability to control fire.
Apparently, he manipulates it by giving it mental commands. He can control the heat, size, and intensity of any flame (including extinguishing it if need be), as well as causing it to form shapes and do what he wills.
Pyro appears to be fairly easy to get along with, with rare losses of temper. His closest friends without a doubt are Mystique and Avalanche. He has always been willing to help Mystique, most notably on her mission to save Graydon Creed even though he was quite ill with the Legacy Virus. Unfailingly loyal, Pyro has been one of her most reliable colleagues. Avalanche is clearly his closest friend, however. Their relationship had a rocky start, and Avalanche put a heavy strain on their later strong friendship. He left Pyro and Blob behind in Kuwait, but afterwards seemed truly contrite and eventually Pyro forgave him. It is possible that Pyro acquired Legacy while he was in Kuwait. Pyro himself was diagnosed not long after returning to the United States. Avalanche feels somewhat guilty about his role in this; he very recently joined up with his friend in order to find St. John a cure.