What?

Powermodding usually means a mod who is very hands-on, to a point where they interfere with normal discussions for dubious reasons. Like closing any thread that vaguely resembles something that's been posted before. This might go as far as muting or banning people for nonsense reasons, power-tripping.

That's kind of difficult to ignore, don't you think? And where does karma come into this anyway?

My understanding is power modding is when someone is a mod in many popular communities and is heave handed when it comes to rules in stead of being soft handed.