Games like The Dark Protocol
Games like The Dark Protocol include Resident Evil Village, Resident Evil 7 Biohazard, Resident Evil Requiem, Dead Space, and Outlast. We matched them by the tags players give The Dark Protocol on Steam (Action, Action-Adventure, 3D, First-Person, and Minimalist): closest matches first, and among equally close ones the better-known games.

Resident Evil Village
Shared: Action · First-Person · Horror

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

Resident Evil Requiem
Shared: Action · First-Person · Horror

Dead Space
Shared: Horror · Sci-fi · Action-Adventure

Outlast
Shared: First-Person · Horror · Atmospheric

Alien: Isolation
Shared: Horror · First-Person · Atmospheric

Five Nights at Freddy's: Secret of the Mimic
Shared: First-Person · Action · Horror

Outlast 2
Shared: First-Person · Horror · Atmospheric

Dead Space (2008)
Shared: Action · Horror · Sci-fi

DOOM Eternal
Shared: Action · Gore · First-Person

DOOM
Shared: Action · First-Person · Gore

Five Nights at Freddy's: Security Breach
Shared: First-Person · Horror · 3D

Dead by Daylight
Shared: Horror · Gore · First-Person

SILENT HILL: Townfall
Shared: Action · First-Person · Horror

The Callisto Protocol™
Shared: Horror · Action-Adventure · Sci-fi

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

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

Lethal Company
Shared: First-Person · Horror · Sci-fi

METRO 2033 Redux
Shared: Action · Atmospheric · First-Person

DOOM 3
Shared: Action · Horror · First-Person

SOMA
Shared: Horror · Atmospheric · Sci-fi

BioShock Infinite
Shared: Action · First-Person · Atmospheric

Choo-Choo Charles
Shared: First-Person · Horror · 3D

Resident Evil 2
Shared: Action · Horror · Atmospheric