I killed him alot with my touch ranger in PvE. That topic is still out there
This should pretty much work for evry proffesion though:
Hug the wall, pull his group, go stand in the Luxon Priest healing range and kill his minions ( aka other enemy's ) first. After it go on the boss wich should firing at a wall.
From this point you can do several things.
Run up to him and kill him ( Warrior/Assassin )
Cast him to death with empathy/SS/other skills ( Casters )
Touch him to death ( R/N, 16 expertise, 12 blood magic )
Willing to show you if you want, best add 1 of my chars to friends list and say from where u got me ( lol, got to much odd people whispering me ^^ ) ill be online in like 1 hour minimum.