Mutation side effects:

-Subject injected/consumed by the mutation would turn into a child of 7 years for 24 hours.

-Subject can regrow any body part no matter how severe the damage is.

-Subject can turn invisible

-Subject cannot feel pain no matter how painful

-Subject's hair colour would change (Ik totally random but its side effects so yea)

-Mutation is permanent and cannot be removed, physically, surgically, etc

Meet serial designation X, or just X for short. They use both he/him and she/her pronouns but prefers she/her pronouns. She is also controlled by the AbsolouteSolver (i think i spelled that wrong but idc) but can control it. He doesn't burn in sunlight