- This level occupies the map slot MAP02. For other maps which occupy this slot, see Category:MAP02.
MAP02: Return to the Darkening is the second map of Claustrophobia 1024. It was designed by Chris Harriman (Impboy), with edits by Walter Confalonieri (daimon), Joonas Äijälä (Jodwin), and Brett Harrell (Mechadon), and uses the music track from GothicDM 2 MAP12 by Mark Klem.
- Letters in italics refer to marked spots on the map. Sector numbers in boldface are secrets which count toward the end-of-level tally.
- In the room with the crates, the wall in the corner behind the mass of crates can be opened. In the corridor behind it is a teleporter that will take you to the top crate, where you can grab a rocket launcher and some rocket ammo. (Sector 239)
- In the same secret is a computer panel with a red light in it. Pressing on the light will teleport you to another corridor where a computer map and a soul sphere are available. (Sector 263)