World 5-2 (New Super Mario Bros. Wii)

World 5-2 is the second level in World 5 in New Super Mario Bros. Wii. It starts off with a number of wigglers. The player will then progress through a green warp pipe into an underground area filled with Mega Wigglers, Swoopers, and toxic purple liquid.

Layout
Before the underground section, the player will have to progress in an area full of wigglers. In the area is a POW Block, allowing to defeat most of them, however, they shouldn't use it near the warp pipe if they want the first star coin, which requires bouncing on a wiggler to get, except if they are playing in multi-player mode. Once in the underground section of the level, the player will see another star coin floating above the so-called "soda" which requires to bounce on a big wiggler to get, and will find more big wigglers as they progress through the cave. After that, they will have to cross a river of poisonous water, having the wigglers making it easier. If the player uses a wiggler to bounce on the ceiling at at certain point, they will realize that there's a secret area with two propeller blocks necessary to get the last star coin, encased in the same room. They will then finally reach the warp pipe leading to the exit. Next to the Flagpole is another big wiggler which can be used to get on top of it and earn an extra life.

Star Coins

 * Star Coin 1: The first Star Coin is not far from the start of the level, floating high above a Wiggler on a platform. Mario and co. can either jump to the Star Coin from the Wiggler, or use the POW Block in the hidden area in the wall to make the Star Coin fall to the ground.
 * Star Coin 2: The second Star Coin is in the beginning of the second area, floating over the Poison Water. Mario and co. must wait for a Big Wiggler to get in the Poison Water, then use it to jump up to the Star Coin.
 * Star Coin 3: On top of the rock ceiling with the third, fourth and fifth Swoopers is a secret area, which Mario and co. must jump to using Big Wigglers. Once there, Mario and co. will arrive at an area with two Propeller Blocks, several Coins, and the third Star Coin, floating high-up in the air. Mario and co. should use one of the Propeller Blocks to fly up to it.

Enemies

 * Wigglers
 * Big Wigglers
 * Swoopers