World 2 (New Super Mario Bros.)
World 2 is the second world in the game New Super Mario Bros. It is a large Desert-themed world, with enemies such as Pokeys and Lakitus. Bowser Jr. is fought here for the second time in the Tower, and the boss of this world is Mummipokey. This world introduces the idea of Warp Pipes - a means of transportation from one level to another. Unlocking Warp Pipes means that the player can skip some levels, and complete the world without completing all the levels.