World 6-4 is a level from World 6 which appears in New Super Mario Bros. Wii. Monty Moles are a common sight in this course. The player will also be able to use Yoshi here. Either Yoshi or a Propeller Mushroom is required for all three Star Coins (Propeller Mushroom is recommended).
The course has rocky mounds which Monty Moles pop-out of. There are also weight-like platforms which will fall down if there is too much weight on one side. The Monty Moles can also cause the weights to tilt and fall. Right after the Checkpoint Flag the player can go below the next platform into a Warp Pipe and obtain a Star Coin.
- Star Coin 1: The first Star Coin is floating above five Coins and a Koopa Troopa.
- Star Coin 2: Directly after the Checkpoint Flag, there is a hidden area with Coins and a Green Pipe below normal ground. Entering the Pipe leads Mario and co. to an underground area with a POW Block which can be used to make the second Star Coin, along with several other Coins, fall to the ground and become obtainable.
- Star Coin 3: Once reaching the cave area, above the first set of weight platforms is a hidden area, and the third Star Coin is right in the middle of it.