My avatar is one I have used for absolutely years. It goes back to a football forum I used to belong to in England. I was one of the Mods on the forum and was known for being strict with idiots on the board trolling. These trolls were know as "numptys" and I became known as the "DEATH of Numptys" an allusion to DEATH in the Terry Pratchett books. I adopted the avatar as a tongue-in-cheek reference to that and I've been using it ever since...
I gotta ask, what or who is your avatar?
The reason I ask is because growing up I read Marvel Comics and one of their characters is a hero known as Moonknight or was it Moon Knight? Anyways your avatar looks like him.