The Blade of Sacrifice is the ritual dagger of Boethiah’s cultists – darker than a normal ebony dagger, lighter, and designed for one grim act.
How to get it
Every worshipper at the Sacellum of Boethiah carries one, so you can collect several during the Daedric quest “Boethiah’s Calling”. When you first arrive, two cultists are already fighting – one dies, and you can loot a free copy from his body.
What it does
Boethiah orders you to sacrifice a follower at the Pillar of Sacrifice. Used for that, the blade kills the victim with a single hit. Otherwise it’s a normal dagger – and you don’t actually need it for the sacrifice; any weapon or Destruction spell will do.
Stats
10 damage, 4 weight. It looks like an ebony dagger but with fewer etchings and hints of green and blue in the light.
Smithing and enchanting
Improvable with an Ebony Ingot, but the Ebony Smithing perk doesn’t help. It can’t be enchanted, and it doesn’t count as an ebony dagger at the Atronach Forge.