The Lightless Ruins refers to an underground fortress built to guard the Lightclaw from the Lightwatchers in 1E931. This underground structure went deep and had a labyrinthian design made to confuse any intruders, built around a central elevator with many puzzles attached to its function. It was guarded by many constructs and gargoyles, and at its deepest point it held a colosseum where the angel Markal Zuriel was in stasis alongside the dagger as its protector.

On the surface, it was an unassuming ruined mound of dirt on the edges of the Everswamp within the foothills of the Kosmosi Mountains, far away from any settlement. Very few were aware of its location and it was purposefully designed to be unassuming and to be forgotten.

In 3E452, the Phoenix Nebula traveled to the ruins on behalf of Emperor Sombra to reclaim the dagger. They passed both the test of Zagho as well as the divine puzzle locking the elevator down into the ruins. Instead of killing Markal, they came to a truce with him, and left the ruins alongside him leaving them devoid of purpose.