Quest: Boethiah's Calling
Reward: Ebony Mail
Location: Southeast of Windhelm
Level requirement: 30
Find the shrine of Boethiah: You receive this quest by encountering a Boethiah cultist on the roads, reading Boethiah's Calling, or stumbling across the Sacellum of Boethiah in the mountains East of Windhelm.
Find the cult of Boethiah: Speak to the priestess in front of the fighting ring and she will tell you must bring someone to the shrine who trusts you and tell them to touch the Pillar of Sacrifice. Once they are trapped by its magic, you are to slay them. Boethiah will then choose if she wishes to speak to you.
Lead someone to become trapped by the shrine and slay them: You can bring any follower you wish, but the best choice is toe simply fast-travel to The Bee and Barb in Riften (or another inn if you like) and hire the mercenary at the corner table for 500 gold. Travel back and instruct him to 'activate' the pillar. He is trapped by Boethiah's magic, so slay him with the Blade of Sacrifice.
Speak to Boethiah's conduit: Boethiah now possesses the body of your dead hireling, and speaks first to you, then to all the cultists, saying that the last man (or woman) standing will be granted a special task.
Slay the other cultists: Stand back and let the other cultists kill each other off as much as possible. When there are one or two left, wade in and slaughter them. Boethiah will reappear to you and tell you that she is displeased with her previous champion and wants you to go to Knifepoint Ridge and kill him and his bandit crew stealthily.
Slay everyone at Knifepoint Ridge stealthily: Travel to Knifepoint Ridge, Northwest of Falkreath, and do your best to kill the bandits outside quietly, though you can also just charge in and kill them all in whatever way suits your character. Inside the mine, do the same thing, though having a stealthy character makes it much easier, because Boethiah's champion is quite tough in one on one combat.
Retrieve and equip the Ebony Mail: Search the champion's body, retrieve the Ebony mail and the rest of the ebony armor if you wish, put it on, and Boethiah will speak to you one last time.