The Abyss is a location in Tyranny.
The Abyss Information
General Walkthrough and Tips
When you reached Abyss, some men sent by Wagstaff is chasing Reef-Talon. But after you showed up, they turn to fight you and Reef-Talon runs away.
Kill the enemies, you will find a Lazu Torchkey from their body which allows you further explore this place. Use the Warden Key and Lazu Torchkey to activate crystals from a distance will create passages.
Explore the west side first, you will need to teleport to Fractured Depth and acquire Cymo Torchkey (it's at lower part of the area, on a body), once you have the Cymo Torchkey, you can explore the east side of The Abyss.
Once you find the Jadis TorchKey at Darkened Hollow, return to The Abyss to activate the passage to center. (Left Crystal-Lazu Torchkey, Middle-Jadis Torchkey, Right Crystal - Cymo Torchkey)
Tanza Torchkey can be acquired from Lexeme once you unlock the middle passage.
A chronicle can be found in the chamber next to the western portal.