World 8 (New Super Mario Bros.)
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World 8 is the final world of New Super Mario Bros. Mario and Luigi travel to this world after defeating Monty Tank or Lakithunder, or using the World 8 cannon in World 5. This world is divided into two parts: a "dark forest" area, and a "lava" area; both having their separate Towers and Castles. The two bosses of this world are Dry Bowser; and a resurrected Bowser fighting along with Bowser Jr.
Unlike all the other worlds, this world does not feature secret exits or unlockable courses.