Sounds like a neat paradox for a hero. Start with a character who’s torn between two worlds—maybe a warrior who once pledged to protect but was betrayed, so he swore vengeance. Each flip isn’t just a mood change, it’s a literal shift into a different reality. The costume can reflect that: one side could be a sleek, silver armor with bright, clean lines, the other a darker, jagged armor with worn leather and shadowy patterns. The narrative could explore how each side affects the hero’s decisions, what allies they lose or gain, and whether they truly can reconcile both sides. A good twist might be that the “bad” side has its own code, making the line between good and evil blurry. Keep the costume evolution subtle—like swapping out a cape or a mask—so the player feels the change without a full overhaul. It turns a simple switch into a rich story about identity, consequence, and redemption.