IE, Bend Will (lvl 2) is supposed to make an NPC your ally for 30 seconds. The Ebony Blade gets powered up when you use it to kill your allies. One could presume, then, that one could use Bend Will to make random NPCs viable targets for the Ebony Blade. I have no idea if this actually works or not though. I'll do some testing later today and see, but I just wanted to see if anyone else has tried this yet.