World 2-3 is the third course of World 2 in New Super Mario Bros. 2. The level takes place underground, and is filled with many moving platforms and pipes.
The level starts in a desert setting with a Pokey and a yellow Warp Pipe that takes Mario to an underground section with floating and rotating platforms, along with several more Pokeys. Past this section is the checkpoint, a Roulette Block, two Coin Roulette Blocks (each with two Spike Tops), and a springboard used to bounce to the higher block. After the checkpoint are two platforms, a Pokey and a yellow Warp Pipe that warps Mario to the next area.
This second area contains Brick Blocks, Question Blocks and red POW Blocks, followed by platforms that go in opposite directions (two sets move downwards and one set moves upwards), with two Pokeys and a Red Ring. After passing a few more Buzzy Beetles and crossing quicksand, a green pipe blasts Mario out of the cave. Back on the surface, there are several stone platforms with Pokeys floating over a pool of quicksand. Crossing it leads to the flagpole.
- Super Mushroom
- 1-Up Mushroom
- Super Leaf
- Super Star
- Star Coin 1: Just after the checkpoint, there are two Warp Pipes, with the lower one obstructed by Brick Blocks. A Buzzy Beetle can be found on the upper pipe; Mario has to pick it up and go to the lower moving platform (the one without the Pokey) and try to activate the outer POW Block. If successful, a path will open for him to reach and enter the pipe. After entering the room, Mario must go left and drop down the hole. There are many Piranha Plants that pop out simultaneously every few seconds, with the Star Coin on the left.
- Star Coin 2: At the beginning the second area, there is a gap in between the Brick Blocks. Mario needs to carry a Buzzy Beetle to a spot just before the gap, and throw the shell to activate all the red POW Blocks while avoiding the red pipe that spawns Goombas, opening a path to the Star Coin.
Star Coin 3: Upon reaching the Red Ring, Mario has to climb up the third set of downward-moving platforms while moving towards the right to a platform made of Brick Blocks and POW Blocks. Navigating through the path by jumping from platform to platform will bring Mario to the Star Coin.
- Star Coin 3: Upon reaching the Red Ring, Mario has to climb up the third set of downward-moving platforms while moving towards the right to a platform made of Brick Blocks and POW Blocks. Navigating through the path by jumping from platform to platform will bring Mario to the Star Coin.