Where is mystic after you beat thorn in kameo?

the mystic is mushroom cavern go there and she will teleport to treasure cave go there and she will teleport to the badlands there she will become gigantic and will be able to fight as a boss but you must have all the crystal eyes in order to fight her if not you will lose the boss battle.

Above was said by someone, I want to point out that's probably not true as there is no mention of such anywhere else and is probably just the poster's fantasy! Mystic just disappeared , end of story!