|Game(s)||Newer Super Mario Bros. Wii|
Newer Super Mario Bros. Wii Plus
|Previous level||(9-8) Purple Sewer|
|Next level||(9-10) Black Clappers|
Grey Mountains (or World 9-9) is the ninth level of Special World from Newer Super Mario Bros. Wii and Newer Super Mario Bros. Wii Plus, and the penultimate level of both games. It is unlocked by completing 9-8: Purple Sewer and finishing that will unlock 9-10: Black Clappers. This is the Angry Sun and the Mad Moon's final appearance.
- Star Coin 1: Before the checkpoint, toss a nearby Koopa Shell at it.
- Star Coin 2: When at the frozen coins section, you'll need to melt the ice to access it. If you don't have a Fire Flower, you'll have to lure the Angry Sun to do it for you.
- Star Coin 3: Shortly after, you'll need to be Super Mario to break the blocks blocking it. A Super Mushroom can be found in a ?-Block.