Level 100 Animate Weapon of Ranged Arms Necromancer^3.28

Notes

For the spectres you can use the Stygian Silverback (from The Riverways in Act 2), the Perfect Forest Warrior, the Perfect Warlord, The Perfect Forest Tiger and the Perfect Hulking Miscreation (the last four spectres are itemisied and can be found in Rituals or 
bought from trade). 

Bladefall of Trarthus and the Arcanist Brand setup will heavily drain your ES so avoid can't regen mana/es/life + reduced defences/recovery (from altars/map mods).

Flesh and Stone is only effective at close range, for accurate long-range EHP deactivate the gem or switch to Blood Stance in PoB.

In the bossing setup Predator can be replaced with Added Chaos Damage if you don't want to use signal prey or with Unleash to speed up the summoning process (e.g. for re-entering Invitations after death). For tough, dense maps you can keep using 
Pierce + Volley/GMP instead of Void Manipulation + Greater chain to improve clear speed.

Alternatively you can use lvl 4 Empower in the Bossing setup (instead of Critical Damage) and Annihilation+Pierce in the mapping setup (instead of Critical Damage and Void Manipulation). This is optimal for clear speed but will cost you ~12% dps while bossing.