Developer starlit studio recently put up a Linux demo for Solace Creek, a retro-styled horror game that has a focus on suspense, exploration, stealth & puzzles. If you love dark games with a thick atmosphere, this may be one for you.
No release date is being shared yet, as the developer continues working on expanding it but they said they had many requests for a Linux demo so they've put one up. They've recently been overhauling a number of things in the game including real-time lighting and shadows, along with an upgrade to Unity 6.
Check out the teaser demo trailer below:

Direct Link
More from the Steam page:
You awaken in a strange, abandoned research station. Disoriented and alone, clutching a handful of mysterious crimson coins. But you're not truly alone... Something lurks in the shadows, watching your every move.
The Secrets of TARASET Station
Something terrible has happened here... But what is this place? And how did you get here?
An unsettling Shadow
A sinister entity dwells in the station's dark corridors, drawn to noise and light. Hide when necessary and try to escape this nightmare.
Will you escape this dark place... or become its prey?