We have gone from every level having a unique texture to every level having the exact same texture and only using that one texture. With geometry being the only difference, these levels will probably soon be a blur! Cat's Eyes has a ton of rooms, Damnation has two long corridors, and Darkness is basically a bunch of interconnected corridors in a similar (but slightly more complex) manner to Death's Arrival.
Appears on these pages
Darkness is a Single Player level in Q2. This level has the same geometry as Showdown, though...