Fully clear the Catacombs.
The Catacombs is an area in Act 3. This area does not have a waypoint and is connected to The Marketplace.
Similar to The Crypt Level 2, this area is a maze of rooms that ends at a large bridge. In rooms with bottomless pits, Ink Spinners will climb up from the darkness and attack players. Monsters deal primarily cold damage and necromancers use the curse Frostbite, so high cold resistance is strongly recommended.
A Trial of Ascendancy can be found here.
/remaining displays how many monsters remain alive in the current area.