It's not overpowered though.

For instance against a dedicated duelist like Asher, he probably wouldn't last one minute, since he can easily and very quickly overwhelm him with essentially a 2-man assault, and variable moveset. The semblance seems better fitted against large groups and in long engages.

That being said, it is overpowered in the sense that he just has to hide for 5 minutes to win a fight, which is incredibly boring. In the case of my two characters Krahe and Shaoqing, who both fulfill the same role as he does in their respective teams, they are much more useful, and fair, simply because they can act much sooner than 5 minutes. Shaoqing requires the right moment to assassinate his targets with his lightning blades, and Krahe wittles down his opponent by dancing around them and just out of reach while throwing his needles at them, his semblance letting him escape bad situations.

[@Shadow Daedalus], I have a better idea for your character's semblance. Why not make them into a sniper who thrives in the shadows? Maybe his semblance drains the light from immediate chosen areas, so he can hide in plain sight and fire off his arrows and reposition from relative safety and unexpected positions. Maybe it can even be used to hide one or two allies to help them move in.

A 5 minute timer for a battle where your objective is to wait, hide, and stop them from finding you, is pretty boring, not to mention is very difficult to work in an RP, as it's very hard to keep a timer to figure out when time is up.