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

 is the Tower level of World 4 of New Super Mario Bros. Wii. Defeating Wendy O. Koopa unlocks World 4-4, while finding the hidden goal unlocks the Warp Cannon.

Layout
This tower begins with Conveyor Belts that causes four Iron Blocks to fall, allowing the player to progress. A Dry Bones and a ? Block are found on the right side of the area. A Warp Pipe is at the top of the area, with two Dry Bones with ? Blocks on either side. The next area contains a pipe that creates Iron Blocks, which are used to reach the platform above. More Conveyor Belts follow, with a large group of coins above one. The midway point follows some Conveyor Belts. Following this is a Red Ring, as well as Propeller Blocks and lifts that allow the player to reach the top of the area. Dry Bones are found on platforms next to the walls.

The next area contains Conveyor Belts, as well as more Iron Blocks that act as obstacles as the player climbs the area. At the top of the area, the pipe that creates the Iron Blocks is found, along with a Warp Pipe. There is a hidden section behind a wall to the left of the area containing a 1-Up Mushroom, which can only be accessed by Mini Mario. Through the Warp Pipe, Conveyor Belts drop a large amount of Iron Blocks, which act as platforms to reach the top of the area. The red doors are found at the top, with coins and an Invisible Block containing a Fire Flower in the wall to the left.

Wendy O. Koopa is fought here, behind the red doors. Wendy attacks Mario by shooting rings that bounce off the walls (they eventually dissolve) out of her wand and jumping. She spins around in her shell attempting to hit the player when hit. After being hit the third time, Wendy is defeated.

Star Coins

 * Star Coin 1: The first Star Coin is at the start of the second area, floating high-up. Mario and co. should get on top of an incoming Iron Block and jump from it to reach the Star Coin.
 * Star Coin 2: Directly below the midway point is a hidden area that conceals the second Star Coin. It can be reached with the conveyor belts.
 * Star Coin 3: When entering the area with Wendy's door, the third Star Coin is floating to the high-left. To get it, Mario and co. must jump onto every Iron Block as it falls down, working up to the Star Coin. Once the second-last one falls, Mario and co. should hurry and grab the Star Coin before the last Iron Block falls.

Hidden goal

 * In the last room, there are many Iron Blocks which are about to drop. The player should dash for the left wall before the Iron Blocks fall. They should then jump into a hidden alcove in the wall with a Warp Pipe. The pipe leads to the tower's rooftop which contains the hidden goal. This exit takes the player to the Warp Cannon, which takes the player to World 6.