I have a couple questions.
1. If someone were facing the user, but was in a trance (due to heavy thought, hypnosis, drug use, transcendental meditation, etc.), could the user use this power? I mean, if the other person's in a trance, then they're not observing the user, right?
2. Could the user use this power in conditions such as pitch darkness (provided nobody had night vision/night vision goggles) and heavy fog?
3. If the user were confronted by people, and he or she used smoke bombs, flash bombs, etc. to blind the crowd, could he or she use this power despite there being people in the room?
I'm not trying to split hairs. My hobby is making my own comic books, and I'm seriously considering giving a character this power. I honestly think this is one of the coolest powers I've seen on here in a while. :-D