I used to solo farm in Jarin Plains HM with my derv, VoS build and high scythe mastery. Casters are easy to kill or low armor and for i can have VoS on eternally and regen also. Nice drops sometimes. There u can also farm those insect warriors, group of 2/3 max, let them allineate and u can recover 25 hp each hit, means 75 if 3 of them.
130hp build works also in UW, with the only problem of nightmares stripping and then u are dead
.....But u can kill 3 aatxe in 1.30 min using the right build.
Undead are also easy for derv since u got many holy-dmg skills, like Avatar of Balthazar, earth of the hoy flame, zealous renewal, eternal aura to keep up Avatar of Balthy.
Btw, a good derv can solo farm every kind of casters, the only problem are some mesmers in HM using singet of humilty, which makes VoS disable for some secs and u'are really, really in troubles!
Ranger are also easy to farm; just put on Avatar of Melandru and their conditions are useless, Wild blow to remove any stance like escape etc etc...
Warriors: Ebon Dust Aura (E), cloack of dust to deal ebon dmg and they are blinded every attack skills u use for many secs.
Sins: Fleeting stability, regen, mystic vigor, high scythe mastery, wild blow, ebon dust aura (E) also good.
Monks: Grenth's Aura, intimidating aura to remove enchants, reaper's sweep/wounding stryke, aura of thorns, wild blow (which result always in a critical, means I dealt up to 130 dmg in PvP to some monks)
Derv: IDK
