Games like The Black Within
Games like The Black Within include Poppy Playtime, Mouthwashing, SOMA, Sally Face - Episode One, and No, I'm not a Human. We matched them by the tags players give The Black Within on Steam (Horror, Psychological Horror, Dark, Psychological, and Survival Horror): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Horror · Dark · Psychological Horror

Mouthwashing
Shared: Horror · Psychological Horror · Psychological

SOMA
Shared: Horror · Psychological Horror · Dark

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

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

Phasmophobia
Shared: Horror · Psychological Horror · Dark

Outlast
Shared: Horror · Psychological Horror · Survival Horror

SILENT HILL 2
Shared: Horror · Psychological Horror · Survival Horror

Outlast 2
Shared: Horror · Psychological Horror · Survival Horror

Visage
Shared: Horror · Psychological Horror · Dark

MiSide
Shared: Psychological Horror · Horror · Story Rich

Blair Witch
Shared: Horror · Psychological Horror · Dark

Layers of Fear (2016)
Shared: Horror · Psychological Horror · Story Rich

Little Nightmares II
Shared: Horror · Dark · Psychological Horror

Darkwood
Shared: Horror · Psychological Horror · Survival Horror

Little Nightmares
Shared: Horror · Dark · Adventure

Five Nights at Freddy's 2
Shared: Horror · Psychological Horror · Survival Horror

Garten of Banban
Shared: Horror · Psychological Horror · Dark

Amnesia: A Machine For Pigs
Shared: Horror · Psychological Horror · Story Rich

Fran Bow
Shared: Psychological Horror · Horror · Dark

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

What Remains of Edith Finch
Shared: Story Rich · Mystery · Psychological Horror

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

The Cat Lady
Shared: Horror · Psychological Horror · Story Rich