Best way that I found to take him down easily is to go about it in a tradtional mmo way. A group of at least 4 or 5. 2 people fight him at close range, 1 person shoots him or blasts him with the staff, and 2 people heal and do voodoo damage. But, make sure that each healer has the other healer attuned in case the boss tries to run at him/her.
I was, however, able to duo him with a friend of mine. It was no easy task and took like a half an hour. We both used voodoo dolls and ran around in circles damaging him, healing each other along the way.
I love this boss! So fun and challenging. Can't wait for him to actually start dropping some loot!
