Penumbra: Requiem

Penumbra: Requiem is an expansion pack to the game Penumbra: Black Plague. Like the previous games, Requiem is an exploration-based adventure game that takes place from a first-person perspective and is the final installment of the main series. Unlike Black Plague and Overture however, the focus is almost exclusively on puzzle solving. No enemies are encountered, meaning that the player can only be injured by environmental hazards. (wikipedia.org)