Amazon is taking pre-orders for Portal 2 for Xbox 360 or PS3 bundled with a $20 gift card for $54.99 with Free Shipping for a limited time. Portal 2 is a massive sequel to the title named 2007’s Game of the Year by over 30 publications worldwide. The single-player portion of Portal 2 introduces dynamic characters, fresh puzzle elements, and a larger set of devious test chambers. Players explore areas of the Aperture Science Labs and reunite with GLaDOS, the murderous computer companion. The two-player mode features a separate campaign with unique story, test chambers, and two new player characters. This mode forces players to reconsider everything they thought they knew about portals. It features an advanced use of physics to allow for the creation of a whole new range of interesting challenges, producing a much larger but not harder game. This game is scheduled for release on April 21, 2011. The promotional credit will be added directly to your Amazon.com account within two days after your order ships. Offer valid when shipped and sold by Amazon.com.

Walmart is also taking pre-orders for Portal 2 for Xbox 360 or PS3 bundled with a $20 gift card for $54.96 with for a limited time. Shipping adds 97-cents.