This mutation can take a number of forms. The character’s hair color, eye color, skin color (or any combination) can be a color not normally found in humans. Odd hair colors might be light red, unusually fair blond, white, platinum, or silvery gray. Skin hues might include extensive freckling, melanin blotches, irregularly livid tones, etc. Eye colors could be red, pink, white, unusual flecked combinations etc. Other mutations are possible, such as scales instead of skin, general cosmetic deformity, or general animal-like deformity. Whatever the abnormal condition, it is clear that the character is not a normal human or animal.