Games like Gloom
Games like Gloom include Poppy Playtime, Outlast, SILENT HILL 2, MiSide, and Darkwood. We matched them by the tags players give Gloom on Steam (Horror, Simulation, Psychological Horror, Demons, and Adventure): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Horror · Psychological Horror · Survival Horror

Outlast
Shared: Horror · Psychological Horror · Survival Horror

SILENT HILL 2
Shared: Horror · Psychological Horror · Story Rich

MiSide
Shared: Psychological Horror · Horror · Story Rich

Darkwood
Shared: Horror · Psychological Horror · Adventure

SOMA
Shared: Horror · Psychological Horror · Story Rich

Sally Face - Episode One
Shared: Psychological Horror · Horror · Story Rich

Phasmophobia
Shared: Horror · Psychological Horror · Demons

Outlast 2
Shared: Horror · Psychological Horror · Survival Horror

Mouthwashing
Shared: Horror · Psychological Horror · Story Rich

The Forest
Shared: Horror · Adventure · Survival

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

Visage
Shared: Horror · Psychological Horror · Survival Horror

No, I'm not a Human
Shared: Horror · Psychological Horror · Story Rich

SILENT HILL f
Shared: Horror · Psychological Horror · Story Rich

Fran Bow
Shared: Psychological Horror · Horror · Story Rich

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

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

MADiSON
Shared: Horror · Psychological Horror · Survival Horror

Little Nightmares II
Shared: Horror · Adventure · Psychological Horror

The Outlast Trials
Shared: Horror · Psychological Horror · Survival Horror

Little Nightmares
Shared: Horror · Adventure · Psychological Horror

Blair Witch
Shared: Horror · Psychological Horror · Adventure

The Beast Inside
Shared: Horror · Adventure · Psychological Horror