Void Scythe

Instead of a Blade, a swathe of absolute darkness inimical to life tips this scythe.
This scythe functions as a +1 greataxe. As a bonus action the bearer of this scythe may channel their life energy into the scythe, fueling its negative energy potency. The bearer my consume upto 5 hit die to empower the scythe for 1 minute. For each hit die consumed the scythe does an additional d6 force damage on hit. Once this affect ends the bearer takes d10 force damage for each hit die consumed, as the scythe rips back into reality. While this affect is active, and during its ripback damage, any creature that is reduced to 0hp has their souls removed from their body and sent to the original bearer of the scythe. The body of the creature becomes a feral zombie.

Requires attunement

Image: https://www.hiveworkshop.com/threads/argus-the-unmaker-and-variations.328725/