World 2-Tower (New Super Mario Bros.)

 is the fifth level and the tower of World 2, and subsequently, of New Super Mario Bros.. The boss here is Bowser Jr..

Layout
With the appearance of a few coins and a rotating platform, World 2-Tower begins. The player must jump to the first rotating platform, then to the next one. Above the second platform reside three ? Blocks - two containing coins, while the other contains a power-up. The player must then jump to the rotating platform located above the three ? Blocks. To the player's right is a Dry Bones that may walk upon the rotating platform. The player must then jump to the left, where another Dry Bones is located. Above here is a rope; the player must climb across the rope to a slightly higher location. Up even higher, another rotating platform will be found. If the player jumps to the left, he or she will land on a shallow cliff. From here, the player can repeatedly Wall Jump his or her way up to a door. Behind the door, there is a cluster of gold bricks in the shape of an "n". The player must then wall jump within the bricks nonstop as it rolls along the wire track. At the top, the player must drop out of the brick "n", quickly jump up the platforms, and land on top of the brick "n". The player can then jump to a new platform, nabbing a Star Coin along the way. The player must repeat the aforementioned process in the following brick "n" in order to access another door. The player will then drop into the main area.

If the player doesn't take the door's path, he or she can climb along a rope, activating a Red Ring along the way. Past here, a Spring is found; by utilizing it, the player can access the pipe located directly above. In the next area, the checkpoint is activated directly before a ? Block. As the player jumps across several rotating blocks, he or she will encounter two Dry Bones directly beneath a red pipe. On the other end of the red pipe is a door; and behind that, Bowser Jr. awaits. The battle with Bowser Jr. is the same as the previous one - only this time, the player must avoid falling in quicksand.

Star Coins

 * Star Coin 1 - After the first rope hang is another spinning platform. Wall jumping left of the platform will lead to a door. Behind the door are two golden block formations. The key to obtain this coin is to keep wall jumping off the blocks. When the platform reaches solid ground, jump on top of the formation and get the first Star Coin.
 * Star Coin 2 - After the first rope hang is another spinning platform. Jump over the formation of blocks in the right side. This will lead Mario or Luigi to a Star Coin located at the bottom right corner of the area.
 * Star Coin 3 - Before taking the red pipe to fight Bowser Jr, wall jump off the left side of the wall and then the red pipe to hit a red switch which will cause three platforms to appear. Using these three platforms, collect the last Star Coin.

Enemies

 * Dry Bones
 * Bowser Jr. (boss)