World 7 (New Super Mario Bros.)

World 7 is a New Super Mario Bros. world made up of clouds. The player get there by beating Petey Piranha (boss of World 5 with a Mini Mushroom, or using the Warp Cannon in World 4. It is the first place Banzai Bill appears (in world order).

The boss, a Dark Lakitu named Lakithunder, is speculated to have caused the attack on Princess Peach's castle in the intro movie.

Trivia

 * World 7-2 takes place on a giant Wiggler with precisely twenty-eight body segments, if you count its head, it has twenty-nine.

Enemies Introduced

 * Banzai Bill
 * Flame Chomp
 * Squiggler
 * Flamethrower