Games like The Castle
Games like The Castle include Five Nights at Freddy's: Security Breach, Little Nightmares, Little Nightmares II, Five Nights at Freddy's: Into the Pit, and INSIDE. We matched them by the tags players give The Castle on Steam (Adventure, 3D, Horror, Multiple Endings, and Singleplayer): closest matches first, and among equally close ones the better-known games.

Five Nights at Freddy's: Security Breach
Shared: Horror · Singleplayer · Multiple Endings

Little Nightmares
Shared: Adventure · Horror · Singleplayer

Little Nightmares II
Shared: Adventure · Horror · Singleplayer

Five Nights at Freddy's: Into the Pit
Shared: Adventure · Horror · Singleplayer

INSIDE
Shared: Horror · Adventure · Indie

Escape the Backrooms
Shared: Horror · Adventure · 3D

MiSide
Shared: Horror · 3D · Singleplayer

Poppy Playtime
Shared: Horror · Singleplayer · Adventure

Five Nights at Freddy's: Secret of the Mimic
Shared: Adventure · Horror · 3D

Mirror 2: Project X
Shared: 3D · Singleplayer · Multiple Endings

SchoolBoy Runaway
Shared: Adventure · Horror · 3D

Bendy and the Dark Revival
Shared: Horror · Singleplayer · Adventure

Stray
Shared: Adventure · Singleplayer · Horror

No, I'm not a Human
Shared: Horror · Singleplayer · Indie

Bramble: The Mountain King
Shared: Adventure · Horror · 3D

The Room Three
Shared: Adventure · Indie · Singleplayer

That's not my Neighbor
Shared: Adventure · Horror · Indie

Buckshot Roulette
Shared: Horror · Singleplayer · 3D

Choo-Choo Charles
Shared: Horror · Singleplayer · 3D

Reventure
Shared: Adventure · Multiple Endings · Indie

Firewatch
Shared: Adventure · Singleplayer · Indie

Lucius
Shared: Adventure · Horror · Singleplayer

The Beast Inside
Shared: Adventure · Horror · Singleplayer

The Forest
Shared: Horror · Adventure · Singleplayer