prospero was one of valve original games that never got realaesed, it was in develoupment wehn Half-Life 1 was being made too, but they cancelled it because they had to scrape Half-Life and start over. I personally think that that game had great potential, espically with a girl being the main charactor, i think that it would have been a cool new approch for VALVe, now prospero may have all ready been made with portal, but i think that they should make prospero and use that name and acctully make a FPS, espically with it being like myst, that would have been one hell of a game
keyword for google if you dont know what im talking about is: prospero valve