Games like Backdoors
Games like Backdoors include Firewatch, Backrooms: Escape Together, PEAK, Riven, and Escape the Backrooms. We matched them by the tags players give Backdoors on Steam (Action, Casual, Adventure, Puzzle, and Roguelike): closest matches first, and among equally close ones the better-known games.

Firewatch
Shared: Adventure · Walking Simulator · Exploration

Backrooms: Escape Together
Shared: First-Person · Adventure · Exploration

PEAK
Shared: Adventure · Exploration · First-Person

Riven
Shared: Adventure · Puzzle · Exploration

Escape the Backrooms
Shared: Adventure · Exploration · First-Person

The Forest
Shared: Adventure · Action · First-Person

The Exit 8
Shared: Puzzle · Exploration · Walking Simulator

What Remains of Edith Finch
Shared: Walking Simulator · Adventure · Exploration

Inside the Backrooms
Shared: Puzzle · Adventure · Exploration

Blue Prince
Shared: Puzzle · Exploration · Adventure

Outer Wilds
Shared: Adventure · Exploration · Puzzle

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

Quern - Undying Thoughts
Shared: Adventure · Puzzle · Walking Simulator

Rise of the Tomb Raider™
Shared: Action · Adventure · Exploration

The Witness
Shared: Puzzle · Exploration · First-Person

Tomb Raider Game of the Year
Shared: Action · Adventure · Exploration

Big Walk
Shared: Puzzle · Adventure · Exploration

VLADiK BRUTAL
Shared: Action · Adventure · Casual

Lorelei and the Laser Eyes
Shared: Adventure · Puzzle · Action

INFRA
Shared: Puzzle · Exploration · Adventure

Poppy Playtime
Shared: Puzzle · First-Person · Adventure

The Room 4: Old Sins
Shared: Puzzle · Adventure · Mystery

Five Nights at Freddy's: Security Breach
Shared: Action · Adventure · First-Person

We Were Here
Shared: Puzzle · Adventure · Action