Penumbra is described as ': Overture is the first in a series of episodic survival horror games developed by Swedish developer Frictional Games. It was originally intended as the first episode of a trilogy'. There are more than 10 games similar to Penumbra for a variety of platforms, including Windows, Mac, Steam, Linux and Playstation. The best alternative is Left 4 Dead. It's not free, so if you're looking for a free alternative, you could try SCP: Containment Breach or Cry of Fear. Other Penumbra like games are Amnesia: The Dark Descent (Paid), Resident Evil (Paid), Dying Light (Paid) and Silent Hill (Paid).
A procedurally-generated apocalypse in which only The Light can save us. Use stealth and evasion to avoid terrifying machines that patrol the desolate world, and employ the powers of Light to unpick their deadly traps.