I couldnt one-hit anyone last night. Didnt even take 50% of their HP, and that was using Buld Up + Assassin's Strike (Fought blasters and scrappers mainly). Admittedly I dont even have any DO's on any of my powers yet (2 TO Acc, 3 TO Dmg). My main problem in PvP (espacially one-on-one) is running out of endurance. I was taking very little damage from anyone I was fighting yesterday and was inflicting alot, but lack of endurance forced me to disengage every time (Still no hero kills under my belt

). Either I had to run fromn lack of endurance or the hero screamed "OmG a st4lker!! Runxxorz!!" and fled flailing their hands like a paragon city cop after one assassin's strike (and, twice, before the assassin's strike because I'd left Stealth off

)
Most of the heroes were exemped lvl 50's though...