Mutagen Medicine is an invention of Donatello. This liquid is a medicine that was made for Leonardo, which contains Mutagen in it. Mutagen Medicine debuts in Within the Woods.
- The Creep was created and mutated by this substance, since Leonardo vomits.
- According to Leo, this medicine was no good for him and made him want to vomit it out.
- A shrine by The Creep was made for the Mutagen Medicine.
- This references Friday the 13th, because Jason made a shrine of Jason's mom's head.