Frosted Glacier
Template:Worldbox Frosted Glacier is the snowy fourth world of New Super Mario Bros. U, lying northeast of Layer Cake Desert, Sparkling Waters, and Acorn Plains, north of Soda Jungle, northwest of Rock-Candy Mines and Meringue Clouds, and west of Peach's Castle. Frosted Glacier is a cold and snowy world with pine trees and indigo mountains that takes place during a constellation filled night. It's one of two of the worlds that the player can choose from after beating Morton in Morton’s Compactor Castle, the other being Sparkling Waters. Because of this, it is quite possible to play through the game without ever reaching Frosted Glacier. There are 9 levels in this world, five of them are the regular levels, two are the Tower and Castle levels, one Ghost House, and one secret level. The name is derived from frosting, or a reference to the original meaning, which is to be covered and coated in frost. The boss of this world is Wendy O. Koopa. The Bubble Baby Yoshi makes their appearance on the map. There are Cooligan Enemy Courses.
Levels
| Level Number | Level Name | Preview | Description |
|---|---|---|---|
| Frosted Glacier-1 | Spinning-Star Sky | File:Snow Star lands NSMBU.jpg | A snowy level that includes giant stars that spin when the player steps on it. |
| Frosted Glacier-2 | Cooligan Fields | 
|
A frosty level that introduces Cooligans. |
| Frosted Glacier-File:Fort Icon.png | Freezing-Rain Tower | File:FeezingTower.jpg | The Tower of Frosted Glacier. Boom-Boom is the boss of the Tower. |
| Frosted Glacier-3 | Prickly Goombas! | File:PricklyGoombas!.jpg | A frosty level that introduces Prickly Goombas. |
| Frosted Glacier-4 | Scaling the Mountainside | File:Snow Mountain NSMBU.jpg | A snowy level that includes Weight-Platforms and Bullet Bills. |
| Frosted Glacier-5 | Icicle Caverns | File:World4-5StarCoin1.jpg | A icy cave level with falling icicles. |
Frosted Glacier- Ghost House
|
Swaying Ghost House | File:World4-HStarCoin1.jpg | A ghost house that constantly moves. |
Frosted Glacier- Castle
|
Wendy's Shifting Castle | File:NSMBU4PlyBoostMode.jpg | A castle with moving girders and Thwomps. |
| Frosted Glacier-Fliprus | Fliprus Lake | File:World4-AStarCoin2P1.jpg | A secret course introducing Flipruses. |
Challenge Mode Original Courses
- Bullet Bill 1-Up Bounce - 1-Up Rally
- Fliprus Crossing - Time Attack
- Ghost House Coin Curse - Coin Collection
- Icicle Skating - Time Attack
- Penguin Bowling - 1-Up Rally (Original Course)
- Prickly Goomba's Coinless Run - Coin Collection
- Slick Slopes and Bullet Bills - Time Attack
Boost Rush Courses
- Spinning Star Sky – Flying Squirrel Pack
- Wendy's Shifting Castle – Acrobat Pack
- Fliprus Lake – Penguin Pack
- Cooligan Fields – Penguin Pack
