I am also a 70 nec, which solo's him quite frequently. He is a caster with healing powers, and he will heal himself around 40-50% if he feels he is being outmatched. With a 5-6 second summon pattern, you have plenty of time to snare, Hot, and pet attack before the first, then take off and dot him up, continue to avoid him after each summon, and tap in between. Leaving some corpses laying around for WTD will help with his healing attempts, and don't be afraid to burn him down.. If you don't stop him from healing, you will waste double the mana trying to win. In my experience, he, and all other NC mobs summon around 66%
Reincarnate
70th Necromancer of Bertoxx