Games like Biological Incident
Games like Biological Incident include Summer of '58, MiSide, Layers of Fear (2016), SOMA, and What Remains of Edith Finch. We matched them by the tags players give Biological Incident on Steam (Exploration, Simulation, Walking Simulator, 3D, and First-Person): closest matches first, and among equally close ones the better-known games.

Summer of '58
Shared: Walking Simulator · Horror · Psychological Horror

MiSide
Shared: Psychological Horror · First-Person · Horror

Layers of Fear (2016)
Shared: Walking Simulator · Psychological Horror · Horror

SOMA
Shared: Psychological Horror · Horror · Exploration

What Remains of Edith Finch
Shared: Walking Simulator · Exploration · First-Person

Scanner Sombre
Shared: Exploration · Walking Simulator · Horror

September 7th
Shared: Exploration · Walking Simulator · Horror

The Exit 8
Shared: Exploration · Walking Simulator · Horror

Mouthwashing
Shared: Psychological Horror · Horror · Walking Simulator

Firewatch
Shared: Walking Simulator · Exploration · First-Person

Phasmophobia
Shared: Horror · Psychological Horror · First-Person

Psalm 5:9-13
Shared: Exploration · Psychological Horror · Walking Simulator

Amnesia: A Machine For Pigs
Shared: Walking Simulator · Exploration · Horror

Still Wakes the Deep
Shared: Psychological Horror · Horror · Walking Simulator

Dollmare
Shared: Simulation · 3D · Horror

Garten of Banban
Shared: First-Person · Horror · Psychological Horror

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

Lethal Company
Shared: First-Person · Exploration · Horror

Visage
Shared: Psychological Horror · Horror · First-Person

Father's Day
Shared: Simulation · Walking Simulator · Psychological Horror

Outlast
Shared: First-Person · Horror · Psychological Horror

Five Nights at Freddy's
Shared: Horror · Psychological Horror · First-Person

Don't Play This
Shared: Exploration · Psychological Horror · Walking Simulator

DON'T SCREAM
Shared: Psychological Horror · Walking Simulator · First-Person