[@The ghost in black] All I really ask is that you don't have "world destroying" powers(ex. The power to make every nuclear bomb on the planet go off at once. Poor example i know). It is an rp based in the human world after all. Your powers can be either magically or genetically gained. Or however they are gotten. Point being prisoners had "inhuman" abilities. Got in trouble. Got locked up in this "one of a kind" prison.
Keep in mind though. The more powerful or aggressive one is the less likely for other inmate or guards to trust them freely. But, theres next to no limits here. Just don't get too carried away. It isn't an inheritely "supernatural" world. 
 
I believe this answers your question too, [@Ghost Queen] That's a fine idea for a character. As long as it doesn't fart anti-matter you'll be fine.

Also, [@The1Rolling1Boy] more than one ability is fine. Just make sure it doesn't know every power in creation.

[@Sleepyhollows] I don't see why not. Just remember. You'd be playing a human. In a prison full of "super powered" people. Don't expect that job to be done very frequently. I can't imagine inmates getting THAT injured aside from the brawls from time to time.