The Prospero development was halted in 1998, was it because of Half-Life ?

Thanks to an interview with Marc Laidlaw by François Aymes for, we can read some more details on the project: In the Half-Life sound files folder (Steam version), the music files commonly known as “Dimensionless Deepness”, “Steam in the Pipes”, “Threatening (Short)”, “Traveling Through Limbo” and “Vague Voices” are named “prospero01” to “prospero05”, which could imply that the tracks were initially made for Prospero. Key features that were planned for Prospero were later integrated in other Valve projects, as Steam and Portal 2. Prospero was canned in 1997 when Valve decided to move their effort to Half Life. Initially the game was meant to be an action adventure, with an “science fantasy epic” storyline, lots of exploration and a complex combat system with psionic powers, but after a while the project became a MMORPG in which Valve wanted to let users to create their own worlds to have an ever-expanding universe. Prospero is a cancelled PC game that was in development by Valve while they were working on Half Life / Quiver.

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