Once your Necromancer reaches level 70 (perhaps with a help of a leveling build), you will be in a prime position to pick and work towards your Build. Keep in mind that your Build will not only define your gameplay going forward, but also your optimal armor and weapons.
Below you can find some of the best Necromancer builds for Diablo III.
Trag’Oul Death Nova
An easy to use and tanky build that specializes in high AoE damage. Damage from this build primarily revolves around Death Nova.
(Also known as “zDH Build” for “zero” damage)
A highly flexible build that enhances the damage of others in your group, and keeps enemies from attacking. This build mainly revolves around spreading Corpse Lance in order to increase the damage of your group.
Keep in mind that this build is only meant to be used in groups, as the Support Necromancer themself will do little to no damage.
Rathma Army of the Dead
A unique build that allows you to literally swarm enemies with the undead. Damage from this build revolves around Army of the Dead, while allowing it to be used as much as possible.