Immortality isn't exactly a superpower you can easily prove to the skeptic. Sure, you can say that you're Really Seven Hundred Years Old, but whose to say that they'll believe you? And, while you may have that Healing Factor, you need to be injured for that to work. It's not like you can have your arm sliced open on demand just to prove that you- Wait a sec, you can. Not to be confused with Self -Harm. Examples of Self-Mutilation Demonstration include: