Legend
A powerful boss named Arbaziloth lurks in the depths of Azzilon, guarding powerful items and unleashing chaos on anyone daring to enter his domain. Only the bravest adventurers will survive the trials of this dangerous quest.
Location
Edron, Azzilon
Dangers
Brinebrute Inferniarch, Gorger Inferniarch, Spellreaper Inferniarch, Broodrider Inferniarch, Sineater Inferniarch, Hellhunter Inferniarch
Reward
Fiend Slayer Outfits and the achievement Fiend Slayer. 
Base Outfit[]
To obtain the base outfit, you need to complete the No Rest for the Wicked Quest.
Addon 1[]
Use a set of Demon Claws 
and you will receive the first addon, these can be looted from Arbaziloth, when killed on easy mode.
Addon 2[]
Use a Demon Skull 
and you will receive the second addon, this can be looted from Arbaziloth, when killed on hard mode.
- Upon receiving both addons, you'll receive the achievement Fiend Slayer.