Games like Vessel
Games like Vessel include PEAK, Escape the Backrooms, Inside the Backrooms, R.E.P.O., and Phasmophobia. We matched them by the tags players give Vessel on Steam (Multiplayer, Puzzle, Online Co-Op, RPG, and Horror): closest matches first, and among equally close ones the better-known games.

PEAK
Shared: Multiplayer · Co-op · Online Co-Op

Escape the Backrooms
Shared: Multiplayer · Co-op · Online Co-Op

Inside the Backrooms
Shared: Multiplayer · Puzzle · Co-op

R.E.P.O.
Shared: Multiplayer · Online Co-Op · Co-op

Phasmophobia
Shared: Multiplayer · Online Co-Op · Co-op

Backrooms: Escape Together
Shared: Multiplayer · Online Co-Op · Co-op

It Takes Two
Shared: Co-op · Multiplayer · Online Co-Op

We Were Here Forever
Shared: Puzzle · Co-op · Online Co-Op

The Past Within
Shared: Co-op · Puzzle · Multiplayer

Lethal Company
Shared: Co-op · Online Co-Op · Horror

Scarlet Idol
Shared: Co-op · Multiplayer · Puzzle

We Were Here
Shared: Co-op · Puzzle · Multiplayer

RV There Yet?
Shared: Co-op · Multiplayer · Online Co-Op

We Were Here Together
Shared: Puzzle · Online Co-Op · Co-op

Content Warning
Shared: Online Co-Op · Multiplayer · Horror

Pacify
Shared: Multiplayer · Co-op · Online Co-Op

Dead by Daylight
Shared: Multiplayer · Co-op · Horror

Labyrinthine
Shared: Co-op · Multiplayer · Online Co-Op

Left 4 Dead 2
Shared: Co-op · Multiplayer · Online Co-Op

DEVOUR
Shared: Multiplayer · Online Co-Op · Co-op

Little Nightmares III
Shared: Co-op · Multiplayer · Puzzle

Tick Tock: A Tale for Two
Shared: Co-op · Puzzle · Online Co-Op

Demonologist
Shared: Multiplayer · Co-op · Online Co-Op

Escape Simulator
Shared: Co-op · Puzzle · Multiplayer