Games like The Deathmind
Games like The Deathmind include Poppy Playtime, Inside the Backrooms, Atomic Heart, The Room, and Outer Wilds. We matched them by the tags players give The Deathmind on Steam (Adventure, Puzzle, FPS, First-Person, and Realistic): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Puzzle · First-Person · Adventure

Inside the Backrooms
Shared: Puzzle · Adventure · First-Person

Atomic Heart
Shared: Adventure · FPS · Puzzle

The Room
Shared: Puzzle · Adventure · Atmospheric

Outer Wilds
Shared: Adventure · Puzzle · Mystery

Half-Life 2
Shared: FPS · Adventure · Sci-fi

Ready or Not
Shared: FPS · Realistic · First-Person

The Room Two
Shared: Puzzle · Adventure · Atmospheric

The Talos Principle
Shared: Puzzle · First-Person · Sci-fi

Firewatch
Shared: Adventure · Atmospheric · First-Person

Black Mesa
Shared: FPS · First-Person · Sci-fi

What Remains of Edith Finch
Shared: Adventure · First-Person · Atmospheric

Sally Face - Episode One
Shared: Puzzle · Adventure · Atmospheric

The Room Three
Shared: Puzzle · Adventure · Mystery

VLADiK BRUTAL
Shared: FPS · First-Person · Adventure

Little Nightmares II
Shared: Adventure · Puzzle · Atmospheric

Little Nightmares
Shared: Adventure · Puzzle · Atmospheric

Firework
Shared: Puzzle · Atmospheric · Mystery

SOMA
Shared: Atmospheric · Sci-fi · First-Person

Return of the Obra Dinn
Shared: Puzzle · Mystery · Atmospheric

Observation
Shared: Adventure · Puzzle · Sci-fi

Scorn
Shared: Puzzle · First-Person · Atmospheric

ROUTINE
Shared: Adventure · Sci-fi · Atmospheric

BioShock Infinite
Shared: FPS · First-Person · Adventure