Bro, I got to tell ya that neither of those names (?) fit ya. And the UlTimZeRo thing sounds way too much like ZeroCool ( and if you don't already know, trust me, you might regret anything close to that name. )
I would suggest a play on your current game name or something that might be a little more reflective of the content you plan to host. Also, personally, I would only try to spell something in L337 $P34|< if I were doing this ten or fifteen years ago. By now, far too many script kiddies and elite downloaders have used Leet Speak names trying to sound cool ( even though that boat sailed years ago. ).
My best suggestion would probably be something like Lex Talionis which is Latin for The Law of Revenge ( an attempted play on your current name. ) Other suggestions of mine might be something like Thanatos ( the Greek god of death. )
Also, you mentioned a sniping video earlier... Well, in Greek mythology, there was an archer named Chiron who was the sniper of the day ( he was known for making incredible shots with his weapon. ) And, after having a fallout with Heracles ( whom later shot Chiron ) Chiron set out to prove to Zeus that he still deserved the status of a god. He did this by making the longest shot ever made… Chiron shot the glass bowl of stars that was over the earth, thus spilling the stars across our night sky. Zeus rewarded Chiron by turning him in to the constellation Sagittarius.
Or maybe you want something that stays along the Nordic lines of your Valkyrie idea ( though, the Valkyrie's were Odin's daughters, so that is why I suggest not using that one in particular. ) But maybe try using something like Mjolnir which was the name of the hammer that Thor used.
I'm not too creative, bro, and my suggestions are not too great. But at this point I am just trying to help ya...
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