Games like Forgotten Depths
Games like Forgotten Depths include Amnesia: The Dark Descent, Outlast, Five Nights at Freddy's: Security Breach, Firework, and Poppy Playtime. We matched them by the tags players give Forgotten Depths on Steam (Horror, Indie, Retro, Atmospheric, and Dark Fantasy): closest matches first, and among equally close ones the better-known games.

Amnesia: The Dark Descent
Shared: Horror · Atmospheric · Survival Horror

Outlast
Shared: Horror · Atmospheric · Survival Horror

Five Nights at Freddy's: Security Breach
Shared: Horror · Survival Horror · Exploration

Firework
Shared: Horror · Indie · Atmospheric

Poppy Playtime
Shared: Horror · Survival Horror · Puzzle

Little Nightmares
Shared: Horror · Atmospheric · Indie

SOMA
Shared: Horror · Atmospheric · Survival Horror

Inside the Backrooms
Shared: Horror · Survival Horror · Puzzle

Lethal Company
Shared: Horror · Survival Horror · Exploration

The Count Lucanor
Shared: Horror · Survival Horror · Exploration

Stay Out of the House
Shared: Horror · Indie · Retro

Resident Evil 7 Biohazard
Shared: Horror · Survival Horror · Atmospheric

Outer Wilds
Shared: Exploration · Atmospheric · Indie

Mouthwashing
Shared: Horror · Atmospheric · Retro

Crow Country
Shared: Horror · Survival Horror · Exploration

The Forest
Shared: Horror · Survival Horror · Exploration

Dead by Daylight
Shared: Horror · Survival Horror · Gore

Stray
Shared: Atmospheric · Exploration · Horror

Darkwood
Shared: Horror · Survival Horror · Atmospheric

Five Nights at Freddy's: Secret of the Mimic
Shared: Horror · Exploration · Atmospheric

Detention
Shared: Horror · Indie · Atmospheric

Amnesia: The Bunker
Shared: Horror · Atmospheric · Survival Horror

Backrooms: Escape Together
Shared: Horror · Atmospheric · Survival Horror

Resident Evil 2
Shared: Horror · Survival Horror · Atmospheric