One of the more powerful builds we ran in the Diablo 4 beta, the Bone Spear + Corpse Explosion Necromancer is a potent protagonist, indeed. Boosted skeletons draw aggro, deal damage, create corpses and regenerate Essence, allowing the Necromancer to drive furrows of destruction through enemy ranks with Bone Spear before massacring everything left with Corpse Explosion. Season to flavor with Bone Shards (a surprisingly powerful basic attack that also regenerates Essence) and either Decrepify or Blood Wave, as you gear dictates.