World 3-4 (New Super Mario Bros. Wii)

World 3-4 is the fourth level of the third world in New Super Mario Bros. Wii. There are hidden blocks in this level which will turn into solid red blocks when the ! Switch is activated later in the game.

Layout
The player starts on an ice platform with a moving ice block in front of them. A Penguin Suit is obtainable from one of the ? Blocks. The player will then meet a red Koopa Troopa and another moving ice block. Further down, there is another moving ice block but this time with a Fire Bro shooting down fireballs. A smaller moving ice block follows, then there are two large ice blocks with ice platforms and red Koopa Paratroopas. After that is the checkpoint, where the player will find two Goombas. This is followed by six fast-moving ice blocks with narrow ice platforms and another red Koopa Troopa. The path then splits into two branches here.

First Exit ("Secret Exit")
This exit is represented by the red flag used for secret exits throughout the game, and is the only exit available if playing for the first time. After the six moving ice blocks, there is a Roulette Block, followed by more moving ice blocks which obstruct the players path. Two Fire Bros. will also try to prevent the player from progressing. At the end is a POW Block, more Koopa Troopas and a large moving ice block. The POW Blocks makes the coins hidden in the aie fall onto the moving ice block.

This exit unlocks World 3-5 and a Red Toad House.

Second Exit ("Normal Exit")
This exit is only available after activating the ! Switch in the World Map, which will be accessible after clearing World 3-5, which means this level must be completed twice to finish World 3. Below the six moving ice blocks is a line of red blocks that can safely be crossed. The player can continue to a red pipe, taking them underground. The player can find a platform of red blocks and ice blocks which can be thrown to collect coins and attack Goombas. A green pipe takes the player to the flagpole.

This exit unlocks.

Star Coins

 * Star Coin 1: The Star Coin is located above the first Fire Bro. It is easier to get it when the solid red blocks are activated.
 * Star Coin 2: In the area with the two large ice blocks, there is a section where the player has to duck from an obstructing ice platform. The player should duck the first obstruction, then continuously wall jump in the hidden area to get the Star Coin and to stay safe when the ice block moves away and then returns later.
 * Star Coin 3: The coin is located below the ledge near the second Fire Bro.

Enemies

 * Koopa Troopas
 * Fire Bros.
 * Koopa Paratroopas
 * Goombas