Advanced physics - Provides the opportunity for a fresh set of engaging obstacles, resulting in a larger yet equally challenging game.
The single-player portion of Portal 2 introduces a cast of dynamic new characters dynamic new characters, a host of fresh puzzle elements, and a much larger set of devious test chambers
Massive sequel - The original Portal was named 2007's Game of the Year by over 30 publications worldwide
Complete two-person co-op - Multiplayer game featuring its own dedicated story, characters, and gameplay
Extensive single player - Featuring next generation gameplay and a wildly-engrossing story