BioShock 2, the first person shooter sequel in the works at 2K Marin, 2K Australia, Digital Extremes and 2K China, is now available for pre-purchase via Steam, Valve announced. Those who pre-purchase the game via Steam will save 10% off the regular price and receive a free copy of Bioshock. If you already own Bioshock, you may send the extra copy to a friend using Steam's Gifting functionality. In addition, a Bioshock 2 Four Pack is available for pre-purchase, offering 10% off the regular price plus four free copies of the original game.