Anti-physical attack build.

I've found that when I farmed Outcasts that this build worked very nicely (listed in order of casting):

Spirit of Failure (to manage energy.)
Distortion (Spammed over and over.)
Reckless Haste (put on same foe as SoF)
Price of Failure
Spiteful Spirit {E}
Ether Feast (as needed)

If you can get Spiteful on 2 foes then it goes pretty fast. In PvP it's a little more dicey.

Well of Darkness would be a great support skill to this build especially in PvP. It would work as long as you have a corpse, and that's sometimes an issue in PvP.