If you can, stone tactics, raise anatomy to 100. Gain necro. Use wraith form for mana leech. Cast curse weapon, this will allow you to stay toe to toe. Your weapon should be a demon/deamon slayer, with HLD and HLA. Spam lightning strike and evade.

Alternately, if you have the resources, get +necro skill items, cast Vamp Form. The Life leech will allow you to stay toe to toe as well. In this case, you would want a demon slayer weapon with hit mana leech, HLD, HLA. Spam evade and lightning strike.