Penumbra games in order

All 3 games of the Penumbra series in the order they came out, from Penumbra: Overture (2007) to Penumbra: Requiem (2008).

1. 
   Penumbra: OverturePC, Linux, Mac · Frictional Games
   7430 Mar
2. 
   Penumbra: Black PlaguePC, Mac, Linux · Frictional Games
   8012 Feb
3. 
   Penumbra: RequiemPC, Mac, Linux · Frictional Games
   6927 Aug