Hit him with what? Advanced Soulfire, Cross ANnih? most/all of a warlocks spells are all single target....

At my level thats an additional 600+- dmg every 2 seconds

This is an easy quest with 1 or 2 shamans . just use your brains and position shamans well :)

I did it with 270 paladin blocking and me on my pyro... To get paladin in on the first stairs i relogged on my 122 lvl shaman to heal him from the other side safe spot and he did the clearing until it was good enough for him to heal by himself and i relogged back on my pyro... After that its just very easy.

Mind that i hit my blocker so we had to do it wall hugging style, you should have no problems like that in non-pvp server.

Sure it takes longer time and paladin has to double heal waste flasks like a lot than with a team but you don't have to wait days or weeks to get a team of 100+ shaman and 200+ pyro online with you to do this easy quest.

Just get the highest barb in this game to rush ur seals. Anti-para potion and he can blindrush all day.