alright so from what i understand, the flames blast out from your mouth yes and you will take damage or only if used when opponent is near you?
and i understand the power of the technique is massive and that as long as the user concentrates on the fire it will continue to hunt down the target until the fire wins or is extinguished. yet when you say that it constantly mutates and changes its movements, do you control what they mutate to and how they move? i presume you do.
oh and finally is this like a stream of fire you need to keep breathing out fire, or is it like you blast out a massive fireball then chill and just focus on it and use it?