The Corrupted Abbey is an uberlevel located in the city of Duncraig which dominates the city's eastern half. On Destruction difficulty, it is notable for being the source of Assur's Bane, a unique ring that provides Purify, a required skill when facing certain uberbosses.
Points of interest
Spread around the Corrupted Abbey are the five lieutenants of Assur: Skinrender, Spinecracker, Eyegouger, Fleshcutter and Bonehexer. On Destruction difficulty, each drops his own demon seal, while the normal Slain Souls and Necromorbs have a chance to drop the unique Ring of the Five. This ring can be cubed with the five seals to create Assur's Bane, the sole source of the skill Purify, which is required to deal damage to certain uberbosses, including Assur, the boss of the Corrupted Abbey itself.