Once you reach level 50 and have chosen a Build for your Necromancer, you will want to start picking out the best weapons to complement it. The weapons or Legendary Aspects are designed to enhance either a specific Skill, a group of Skills, or your overall damage.
Best Necromancer Legendary Aspects
Aspect of Grasping Veins
(Offensive Aspect)
Increases your Critical Strike Chance when using Corpse Tendrils, and makes the Skill cause enemies to take more Critical Strike Damage.
Best Build: Bone Spirit Build
Gives you a consistent damage boost.
Unyielding Commander
(Offensive Aspect)
Causes Army of the Dead to gives all of your Minions much more damage and damage reduction.
Best Build: Minion Build
Gives your Minions a huge burst of increased damage and mitigation.
Aspect of the Great Feast
(Offensive Aspect)
Increases the damage of your Minions at the cost of losing Essence over time per Minion. If no Minions are active, you get the damage bonus instead.
Best Build: Bone Spear Build
Gives you a consistent damage boost.