Tossing hat in the ring.

So basically anything goes, but the stronger the character, the more likely they may get targeted, right? So if a character's most notable trait is say, a superpower tied to intelligence or technology, would they slip under the radar, persay? Are aliens, or advanced androids accepted?

Asking since I'm just curious about what may or may not be okay. And seeing what, from my existing staples of past characters that haven't gotten off the ground, can be used for this. Should a writing sample be required, I can provide one when I get back from class.