2. Ebony Mail
What it does: Heavy armour enchanted with the muffle effect, which can inflicts 5 poison damage per second to nearby enemies.
Where to find it: Septimus Sigmus Outpost among other locations.
How to get it: First you'll need to find and read the "Boethiah's Proving" book, which isn't too taxing as it's located in various places - but for the sake of brevity, you'll always find one in Septimus Sigmus Outpost. Once you read it you can head off on a quest to find Boethiah's Shrine. Once you arrive there, the High Priestess will demand that you to prove yourself by luring some "fresh meat" to the shrine for sacrifice. Do as she suggests by luring a companion and getting them to touch the shrine before you off them, after which Boethiah appears and ask for a new champion. It will all kick off among the cult followers, so instead of getting involved needlessly simply wait til all but one are dead, and then sort him out so that Boethiah declares you her new champion, and tasks you with retrieving the lost Ebony Mail for her. Follow her instructions, kill the necessary foes and you'll get the armour.