Hiding Physical Deformities

Many mutations come with physical deformities. Some mutations are easy to hide, while others are harder to conceal.
Any mutation that alters a creature's physical appearance imposes a penalty on the creature's Disguise checks. For creatures trying to conceal multiple physical deformities or alterations, the penalties stack. A cosmetic mutation imposes a -1 penalty on Disguise checks, while a minor or major mutation imposes a -2 penalty on Disguise checks. Drawbacks do not apply penalties to Disguise checks.