Games like Partum Artifex
Games like Partum Artifex include SOMA, Poppy Playtime, Outer Wilds, Little Nightmares II, and MiSide. We matched them by the tags players give Partum Artifex on Steam (Adventure, Atmospheric, Horror, Puzzle, and Thriller): closest matches first, and among equally close ones the better-known games.

SOMA
Shared: Horror · Atmospheric · Psychological Horror

Poppy Playtime
Shared: Horror · Puzzle · Psychological Horror

Outer Wilds
Shared: Adventure · Atmospheric · Exploration

Little Nightmares II
Shared: Adventure · Horror · Puzzle

MiSide
Shared: Psychological Horror · Horror · Atmospheric

Firewatch
Shared: Adventure · Atmospheric · Mystery

What Remains of Edith Finch
Shared: Atmospheric · Adventure · Mystery

Inside the Backrooms
Shared: Horror · Puzzle · Adventure

Amnesia: The Dark Descent
Shared: Horror · Atmospheric · Psychological Horror

Little Nightmares
Shared: Atmospheric · Adventure · Horror

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

Outlast
Shared: Horror · Atmospheric · Psychological Horror

Layers of Fear (2016)
Shared: Horror · Atmospheric · Psychological Horror

The Room Two
Shared: Puzzle · Atmospheric · Adventure

Detention
Shared: Horror · Atmospheric · Adventure

Resident Evil 7 Biohazard
Shared: Horror · Atmospheric · First-Person

Subliminal
Shared: Atmospheric · Psychological Horror · Horror

Mouthwashing
Shared: Horror · Atmospheric · Psychological Horror

Fears to Fathom - Ironbark Lookout
Shared: Horror · Atmospheric · Psychological Horror

Garten of Banban
Shared: Horror · Puzzle · Psychological Horror

Fran Bow
Shared: Adventure · Psychological Horror · Puzzle

Scorn
Shared: Atmospheric · Horror · Puzzle

The Room
Shared: Puzzle · Atmospheric · Adventure

Amanda the Adventurer
Shared: Horror · Puzzle · Atmospheric