Duriel is one of the four Lesser Evils available in Diablo 4 Season 11, and you have to obtain his Corrupted Horn to gain access to two Divine Gifts that will empower your build.
The Corrupted Horn is obtained by defeating Duriel, but the method is a bit complex. This guide will lay down the steps to encounter Duriel and obtain the Corrupted Horn.
How to get Duriel’s Corrupted Horn in Diablo 4 Season 11
You can encounter Duriel randomly in the Sanctuary, or you can summon him at the Pained Altar. The latter is the best way to secure the Corrupted Horn. I am unsure if you can get the Corrupted Horn of Duriel without having to summon.
To summon Duriel at the Pained Altar, you’ll need two Baneful Hearts. Baneful Hearts are extremely rare and can be found from Tortured Gift of Mysteries chests. These chests can be found all over Sanctuary during Season 11.

You can open the Tortured Gift of Mysteries chests with Abhorrent Cinders. You’ll require 75 cinders to open one chest, and Baneful Hearts aren’t guaranteed. The drop rate appears to be really low, so keep that in mind. Once you have found two, go to the Pained Altar to complete the summoning process.
While Duriel is a strong boss to take down, he is nowhere near as difficult as taking down Azmodan. You’ll either want to dodge as many of his attacks as possible or go for a full poison resistance build. Once you have defeated Duriel, he will drop the Corrupted Horn.
Again, you only get the Corrupted Horn by defeating the summoned Duriel in my experience. I managed to get it on my first attempt, so it could be something that is guaranteed. Once you gain the Corrupted Horn, you’ll find an updated objective asking you to return it to Hadriel.
How to use Corrupted Horn of Duriel in Diablo 4 Season 11
This part is relatively easy. Once you have the Corrupted Horn, visit Hadriel in Heavenly Forge. Submit the item you found, and you’ll be able to unlock Duriel’s Divine Gifts. Duriel has two Divine Gifts to offer: Essence of Pain and Essence of Squalor.