99		Penumbra: Black Plague (Windows, 2008)
44		Wild West Quest (Windows, 2008)
43		Hærfest (Windows, 2009)
43		This is Infinity (Windows, 2009)
40		Red Lake (Windows, 2015)
40		Stay Tooned! (Windows, 1996)
40		Titanic: A Mysterious Undersea Adventure (Windows, 1998)
40		RedJack: The Revenge of the Brethren (Windows, 1998)
40		The Lords of Tantrazz (Windows, 1996)

Notes: Games similar to Penumbra: Overture - Episode 1, Games like Penumbra: Overture - Episode 1, Frictional Games AB, Got Game Entertainment, LLC, Windows, Action, Adventure, Puzzle elements, Stealth, Survival Horror, 1st-person, HPL 1, Newton Game Dynamics, PC, Game Similarities.