World 4 (New Super Mario Bros.)

World 4 is a secret world in New Super Mario Bros.. If Mini Mario or Mini Luigi defeat Mummipokey in World 2 they will go to World 4 instead of World 3.

World 4 is a giant forest with many enemies like Wigglers. Bowser Jr., like in every world, is fought here, and a Ghost House is also located here. Mega Goomba is the big boss of this world.