Games like Decrepit
Games like Decrepit include Five Nights at Freddy's: Security Breach, Outlast, The Forest, Lethal Company, and Amnesia: The Bunker. We matched them by the tags players give Decrepit on Steam (Exploration, Walking Simulator, First-Person, Horror, and Underground): closest matches first, and among equally close ones the better-known games.

Five Nights at Freddy's: Security Breach
Shared: Horror · First-Person · Exploration

Outlast
Shared: First-Person · Horror · Atmospheric

The Forest
Shared: Horror · First-Person · Exploration

Lethal Company
Shared: First-Person · Horror · Exploration

Amnesia: The Bunker
Shared: Horror · First-Person · Atmospheric

Firewatch
Shared: Walking Simulator · First-Person · Exploration

Resident Evil 7 Biohazard
Shared: Horror · First-Person · Survival Horror

The Long Dark
Shared: Exploration · First-Person · Survival

Five Nights at Freddy's: Secret of the Mimic
Shared: First-Person · Horror · Exploration

Sons Of The Forest
Shared: Horror · Exploration · Survival

Metro Exodus
Shared: Horror · First-Person · Action

Amnesia: A Machine For Pigs
Shared: Walking Simulator · Horror · First-Person

Subnautica 2
Shared: Exploration · Horror · First-Person

Slender: The Arrival
Shared: Horror · First-Person · Walking Simulator

What Remains of Edith Finch
Shared: Walking Simulator · Exploration · First-Person

Alien: Isolation
Shared: Horror · First-Person · Stealth

Subnautica
Shared: Horror · Exploration · Survival

Resident Evil Village
Shared: First-Person · Horror · Action

The Beast Inside
Shared: Horror · First-Person · Action

METRO 2033 Redux
Shared: Horror · First-Person · Atmospheric

SOMA
Shared: Horror · Exploration · Atmospheric

The Outlast Trials
Shared: Horror · First-Person · Stealth

Escape the Backrooms
Shared: Horror · First-Person · Exploration

Bendy and the Dark Revival
Shared: Horror · First-Person · Action