Darkwood - Darkwood created by Acid Wizard Studio offers a wonderful combination of Open World, Action-Adventure and Horror-Survival, RPG and Roguelike aesthetics.
S.T.A.L.K.E.R. - S.
The Forest - The Forest is a Horror-Survival game with strong Action-Adventure, First-person Perspective, Sandbox, Co-op, Single and Multiplayer Shooting video game by Endnight Games Ltd.
Age of Survival - Age of Survival by Seattletek is a wonderful new Action-Adventure, Horror-Survival and RPG Simulation and Crafting video game.
Pathologic 2 - Pathologic 2 is an Atmospheric, Horror, and Single-player video game brought to you by tiny Build.
Dead Frontier - Dead Frontier is among the few zombie based video games that you can obtain in your web browser and for free.