whats a good osteo necrotic build that doesnt involve strand?

[kindred perch]

title

maybe I didnt phrase it correctly. I want a void necrotic build, doesnt really need to be osteo, but I dont know what aspects and fragments to use. also what stats should I focus

[half zephyr]

fragments: grenade weaken, grenade dmg gives back melee, lingering vortex, devour duration ; aspects: child and devour