Half-Life: Blue Shift is an expansion pack for Valve Corporation's science fiction game Half-Life.
The game was developed by Gearbox Software with Valve and published by Sierra Entertainment on June 12, 2001.
Blue Shift is the second expansion for Half-Life, intended to be part of a Dreamcast port of the original game.
Although this version was cancelled, the PC version remained in development as a separate product.
It was released on Steam on August 24, 2005.[1]