Games like 27 Survivors
Games like 27 Survivors include OMORI, Firework, No, I'm not a Human, KinitoPET, and Mouthwashing. We matched them by the tags players give 27 Survivors on Steam (Psychological Horror, Mystery, Multiple Endings, Retro, and Atmospheric): closest matches first, and among equally close ones the better-known games.

OMORI
Shared: Psychological Horror · Multiple Endings · Horror

Firework
Shared: Mystery · Psychological Horror · Horror

No, I'm not a Human
Shared: Psychological Horror · Horror · Multiple Endings

KinitoPET
Shared: Psychological Horror · Retro · Horror

Mouthwashing
Shared: Psychological Horror · Retro · Atmospheric

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

SOMA
Shared: Psychological Horror · Atmospheric · Horror

SIGNALIS
Shared: Psychological Horror · Atmospheric · Sci-fi

The Test
Shared: Multiple Endings · Psychological Horror · Mystery

Outer Wilds
Shared: Mystery · Atmospheric · Adventure

FAITH: The Unholy Trinity
Shared: Psychological Horror · Horror · Retro

SILENT HILL 2
Shared: Psychological Horror · Horror · Atmospheric

Endacopia
Shared: Psychological Horror · Horror · Multiple Endings

Iron Lung
Shared: Psychological Horror · Atmospheric · Horror

Poppy Playtime
Shared: Horror · Psychological Horror · Mystery

Lethal Company
Shared: Horror · Psychological Horror · Atmospheric

No one lives under the lighthouse Director's cut
Shared: Psychological Horror · Atmospheric · Horror

Raging Loop
Shared: Mystery · Psychological Horror · Atmospheric

Bad Parenting 1: Mr. Red Face
Shared: Psychological Horror · Horror · 1990's

Stories Untold
Shared: Psychological Horror · Horror · Atmospheric

DISTRAINT: Deluxe Edition
Shared: Psychological Horror · Horror · Atmospheric

The Room Two
Shared: Mystery · Atmospheric · Horror

Subliminal
Shared: Psychological Horror · Mystery · Atmospheric

Firewatch
Shared: Mystery · Atmospheric · Adventure