Complete two-person co-op - Multiplayer game featuring its own dedicated story, characters, and gameplay
Advanced physics - Allows for the creation of a whole new range of interesting challenges, producing a much larger but not harder game
The single-player segment of Portal 2 features a variety of engaging new characters, an array of innovative puzzle components, and an expanded collection of challenging test chambers.
Massive sequel - The original Portal was named 2007's Game of the Year by over 30 publications worldwide
Extensive single player - Featuring next generation gameplay and a wildly-engrossing story