Games like The Gravedigger
Games like The Gravedigger include Poppy Playtime, Phasmophobia, The Mortuary Assistant, Outlast, and Pacify. We matched them by the tags players give The Gravedigger on Steam (Horror, First-Person, Demons, Immersive Sim, and Mystery): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Horror · First-Person · Dark

Phasmophobia
Shared: Horror · First-Person · Psychological Horror

The Mortuary Assistant
Shared: Horror · Demons · Mystery

Outlast
Shared: Horror · First-Person · Psychological Horror

Pacify
Shared: Horror · First-Person · Psychological Horror

Escape the Backrooms
Shared: Horror · First-Person · Psychological Horror

The Escape: Together
Shared: Horror · First-Person · Immersive Sim

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

SOMA
Shared: Horror · Psychological Horror · Dark

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

Lethal Company
Shared: Horror · First-Person · Exploration

Demonologist
Shared: Horror · First-Person · Demons

Buckshot Roulette
Shared: Horror · First-Person · Dark

Visage
Shared: Horror · First-Person · Dark

Bendy and the Ink Machine
Shared: Horror · First-Person · Dark

Inside the Backrooms
Shared: Horror · First-Person · Psychological Horror

No, I'm not a Human
Shared: Horror · Psychological Horror · First-Person

Subliminal
Shared: Horror · Mystery · First-Person

Outlast 2
Shared: Horror · First-Person · Psychological Horror

The Exit 8
Shared: Horror · Immersive Sim · Exploration

Platform 8
Shared: Psychological Horror · First-Person · Immersive Sim

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

The Room Two
Shared: Mystery · Horror · Hidden Object

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