Mine actually comes from when I was playing Ultima Online like 4 or 5 years ago. Back when whoever got the last hit on a monster, got all the fame, and loot rights. All they would have is a death robe, newbie dagger, and an orc helmet(the most dropped item in the game), and would come by and stab the orc at the last minute after me attacking the orc and sacrificing myself.
The name really works in a lot of games tho.
My brother wrote a poem about em before, I just supplied the name.
I'll have to find that.....
Anyway, I think it is original, if you think otherwise, please flame me.