[@Zaphander]

The description of your character's quirk is a little bit vague when it comes to his resistance to damage while transformed, just to make it clearer, how much could he fall before getting any serious damage from say... hitting a concrete sidewalk? As in how high of a building could he jump from without fearing that he would break himself on impact?

Also, since he doesn't breathe while transformed, how long can he remain in that form without suffering choking himself?

Lastly, I suppose that he can only use his phone to alert heroes that he knows the number of, right? Unless he has another way of getting people's phone numbers, without them giving it to him, of course.