Bettomaru is the master of the Way of the Flame who lives in a dojo at the top of Mount Jogaku. You climb through a snowstorm to duel him in the Mythic Tale The Undying Flame, and he teaches Jin the technique during the fight.
He fights like a ronin, with three-hit combos and an unblockable slash, and lights his blade for fast four-hit attacks you cannot block. Once you set your own sword alight from the meteorite and hit him with it, the duel ends.
He wears a mask that looks a lot like Gosaku's Visage. He will not finish you off if you lose, which only he and Lord Shimura do.