Made by Gearbox Software and originally released in 2001 as an add-on to Half-Life, Blue Shift is a return to the Black Mesa Research Facility in which you play as Barney Calhoun, the security guard sidekick who helped Gordon out of so many sticky situations.
Well, Half Life Blue-Shift:
Another expension pack for Half Life, Blue Shift's story is not very interesting and fun, but is a very good too, you control Barney. Calhoun, who is a security guard in Black Mesa. But sadly, is story is short. But still good.