World 9 (New Super Mario Bros. Wii)

World 9 is the final world and a secret world of New Super Mario Bros. Wii. The world is set in space and on a giant rainbow star. Each level in the world is gated and cannot be played until all Star Coins from a certain world are found. Therefore, it is optional to play through. There are, just like most other worlds, eight levels. World 9-8, the final one, has giant Bullet Bills called King Bills. These things cannot be stomped on or defeated but can be evaded. 
== How to unlock ==
The World is unlocked when Bowser is defeated. Although to unlock the levels, Mario must collect all the star coins in one world to unlock one level.
== Levels ==
*World 9-1: It is unlocked by collecting all Star Coins from World 1.
*World 9-2: It is unlocked by collecting all Star Coins from World 2.
*World 9-3: It is unlocked by collecting all Star Coins from World 3.
*World 9-4: It is unlocked by collecting all Star Coins from World 4.
*World 9-5: It is unlocked by collecting all Star Coins from World 5.
*World 9-6: It is unlocked by collecting all Star Coins from World 6.
*World 9-7: It is unlocked by collecting all Star Coins from World 7.
*World 9-8: It is unlocked by collecting all Star Coins from World 8.
== Gallery ==
File:World 9-8 - King Bill - Destructing Wall.png|A King Bill destroying a wall in World 9-8.
== Trivia ==
*The track for World 9 has part of Mario Kart 64's Rainbow Road (Mario Kart 64) from it: https://youtu.be/GV4sil8krog?t=30
de:Welt 9 (New Super Mario Bros. Wii)
es:Mundo 9 (New Super Mario Bros. Wii)
fr:Monde 9 (New Super Mario Bros. Wii)
fi:World 9 (NSMBW)
Category:New Super Mario Bros. Wii Worlds
Category:Worlds