Inside the app
A closer look.
About this app
Made for a clear purpose.
Underhalt is an atmospheric, offline anomaly hunt built around careful observation rather than jump-scare reflexes.
Walk the same subterranean service corridor across twelve night shifts. Learn its baseline geometry, fixture rhythm, signs, doors, and shadows. Then decide: has the corridor changed, or is your own memory becoming unreliable?
FEATURES
- A real-time 3D corridor rendered on device - Twelve authored anomaly families with multiple variants - Deterministic shift generation for fair, replayable runs - A stability system that rewards accurate streaks - Flashlight management and changing visibility - A persistent deviation archive - No ads, no accounts, no in-app purchases, and no network connection
One purchase opens the entire building.
