the soul flame is a fire that is a solid, not a gas. It defeats all whom touch it and it's cloth. All but green and red eyed mystas. The gas around it is also deadly. despite the bad things about this flame, it points it's holder to "the way" called by the mystas. "the way" is where the holder goes to become a hero. Fellon's "the way" leads to where he can save his dieing world, stromatale.
the soul flame came into existance when "the great good" and "the great evil" died, Simotaniously.