Unlocks
Mirror
- Unlocks Secret Rooms
Sources and community notes
- The achievements guide lists concepts among the collectibles (nine earned concepts); see Concepts.
- The achievements guide also mentions entering LIMBOK on the prison cell tablet as a "Secret Knowledge" step. Nothing was found on how this concept relates to secret rooms beyond this page.
Community-sourced (added October 2026, not yet verified in-game). Sources: Steam guide: Achievements guide (updated Jan 11, 2025).