Like the previous games, Requiem is an exploration-based adventure game that takes place from a first-person perspective. Unlike Black Plague and Penumbra: Overture however, the focus is almost exclusively on puzzle solving. No enemies are encountered meaning the player can only be injured by environmental hazards.
The game starts as the last one ends, with Philip sending the 'kill them all' message. As soon as he finishes he is hit on the head by something unseen. The player then controls a character in some kind of tomb. Items need to be collected in each chamber in order to move on to the next. In the journey, the player starts to see familiar places from other parts of the facility and receive communication from a person who later identifies himself as Philip's former adviser, Red, from the first Penumbra game. A communication is received from a member of The Shelter advising that while the Tuurngait does not know that Philip has sent a message to the outside world, The Shelter staff are aware that it has happened. This is contradictory as the member of The Shelter who delivers the message is in fact part of the Tuurngait hive mind.
The game, and the entire series, has two possible endings. One concludes with Philip joining Red in the incinerator from Overture, deeming regular life not worth living. As the rest of Requiem seems to have been a figment of Philips mind, this leaves him dead in the room where the game originally began and where Black Plague ended. Philip can also choose to leave Red to die on his own, and return to the fishing boat which was originally used to take him to the mine in the first place. This seems to be a fulfilling of Red's statement that it is "better to have a story and end it than never to realize it has begun".
With the announcement of Penumbra: Black Plague, the series (originally intended to be a trilogy) was reduced to two episodes due to unidentified problems with the previous publisher, Lexicon Entertainment. After the release of Black Plague there continued to be no indication that the developers intended to expand the series other than a April Fools' Day posting about "Penumbra 3 : Back With a Vengeance", a game which would have featured over the top violence and "an action-filled blood soaked ending!"
The developers did however eventually decide that they would release a third installment in the form of an expansion pack in order to tie up loose ends and more fully utilize some of the series characters. Penumbra: Requiem was officially announced on April 16, 2008. During the expansion's development work also began on what would become Amnesia: The Dark Descent.
Penumbra: Requiem was less popular than the previous games in the series, only earning a ranking of 67 from MetaCritic, receiving a rank of only 62 from MobyGames, and a total score of 62.77% from GameRankings. It did however manage to gain the same four star rating as the previous games received from The Linux Game Tome.
- Interview With Frictional Games – Penumbra/Amnesia (Tgdb.nl)
- Penumbra 3 - BWaV Announced! Frictional Games, April 01, 2008
- 'Penumbra: Requiem' Announced Worthplaying, April 16, 2008
- Frictional Games On Penumbra And The Future Rock, Paper Shotgun, February 17, 2009
- Penumbra: Requiem - MetaCritic
- Penumbra: Requiem at MobyGames
- Penumbra: Requiem - GameRankings
- Penumbra: Requiem - The Linux Game Tome