Editing World 9 (New Super Mario Bros. Wii)

'''World 9''' is the final world from ''[[New Super Mario Bros. Wii]]''. It is a special world unlocked by defeating [[Bowser]] in {{world link|8|bowser|World 8-Bowser's Castle (New Super Mario Bros. Wii)}}. Each of the eight [[level]]s in this world is unlocked by collecting all of the [[Star Coin]]s in the world of the corresponding level number. For example, collecting all Star Coins in [[World 1 (New Super Mario Bros. Wii)|World 1]] will unlock [[World 9-1 (New Super Mario Bros. Wii)|World 9-1]]. Each level features the background and a music track from one of the previous eight worlds. World 9's levels were designed to be some of the hardest in the game. None of the levels have any [[Checkpoint Flag|midway point]]s. The [[Super Guide]] is also absent entirely, even if the player loses eight [[Extra life|lives]] in the same level. To compensate, the opportunity to obtain extra lives is given to players early on in each level, typically in the form of a singular [[Brick Block]] containing a [[1-Up Mushroom]]. The rainbow theme is similar to the [[Rainbow Road]] courses in the [[Mario Kart (series)|''Mario Kart'' series]], with the world map music even being an arrangement of [[N64 Rainbow Road|Rainbow Road]]'s music from ''[[Mario Kart 64]]''. World 9 has a total of 24 Star Coins, which are needed if the player wants to get all five stars on their profile on the file select screen. Unlike in previous worlds, the levels can be played in any order, and no [[Enemy Course]]s, [[Tower|fortress]]es, or [[castle]]s (or levels based on them) appear in this world. This is one of only two playable worlds in the ''Super Mario'' side-scrolling games to not include a true castle level, the other being [[World 9 (Super Mario Bros.: The Lost Levels)|World 9]] in ''[[Super Mario Bros.: The Lost Levels]]'', which is also a bonus world that unlocks after completing the game (however, [[World 9-3 (Super Mario Bros.: The Lost Levels)|World 9-3 in ''The Lost Levels'']] does have a similar theme to the castle levels, though it takes place outside).