Re: I killed a fellow PC last night...
Yeah, AF and Penetrating can be absolutely devastating. I'm pretty sure I wouldn't allow it as a GM - much less use it...
I will say that, as a player, if something like that happens in game - that is, the villians take the gloves 'all the way off' - my heroes will up the ante as well. Beating each other up, captures, even deathtraps are just part of the superhero genre and is to be expected. Killing someone in combat, especially with such lethal attacks, means that this is no longer a superhero story, this is a WAR story.