Games like CONCLUSE
Games like CONCLUSE include Poppy Playtime, Outlast, Little Nightmares, Resident Evil 7 Biohazard, and Little Nightmares II. We matched them by the tags players give CONCLUSE on Steam (Horror, Atmospheric, Singleplayer, Psychological Horror, and Adventure): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Horror · Singleplayer · Psychological Horror

Outlast
Shared: Horror · Atmospheric · Psychological Horror

Little Nightmares
Shared: Horror · Atmospheric · Singleplayer

Resident Evil 7 Biohazard
Shared: Horror · Singleplayer · Atmospheric

Little Nightmares II
Shared: Horror · Singleplayer · Adventure

Five Nights at Freddy's
Shared: Horror · Singleplayer · Psychological Horror

Outlast 2
Shared: Horror · Psychological Horror · Singleplayer

Firework
Shared: Horror · Indie · Atmospheric

Dark Deception
Shared: Horror · Singleplayer · Psychological Horror

SOMA
Shared: Horror · Atmospheric · Psychological Horror

Layers of Fear (2016)
Shared: Horror · Atmospheric · Psychological Horror

Bendy and the Ink Machine
Shared: Horror · Singleplayer · Indie

Sally Face - Episode One
Shared: Horror · Psychological Horror · Indie

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

The Beast Inside
Shared: Horror · Adventure · Singleplayer

Escape the Backrooms
Shared: Horror · Psychological Horror · Survival Horror

The Room Two
Shared: Atmospheric · Horror · Mystery

The Room
Shared: Atmospheric · Singleplayer · Mystery

Garten of Banban
Shared: Horror · Singleplayer · Psychological Horror

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

Ultimate Custom Night
Shared: Horror · Singleplayer · Free to Play

Firewatch
Shared: Atmospheric · Adventure · Singleplayer

Inside the Backrooms
Shared: Horror · Psychological Horror · Survival Horror

MiSide
Shared: Psychological Horror · Horror · Singleplayer