World 6-6 (New Super Mario Bros. Wii)
From the Super Mario Wiki, the Mario encyclopedia
This level begins above ground, with a slope leading to a dark underground cavern. There is a boat with a light that the player can move by rotating the Wii Remote. Cheep Cheeps and Big Cheep Cheeps can be found in the water, which rises or lowers at some points of the level. ? Blocks are found, along with a Trampoline on a platform. Platforms made of Brick Blocks are found, as well as a POW Block. Warp Pipes containing Piranha Plants are found, along with a Brick Block containing a Super Star. The midway point is found on a platform. Following this, another Trampoline is found, along with a section with Swoops. A P Switch on the ceiling causes Blue Coins to appear, and a Propeller Block is found on a platform. More Swoops are found, and a Barrel is found on a platform above. A group of three Fire Bros. is found, along with another Barrel. The player then reaches a Warp Pipe, leading to the flagpole.
A secret exit exists in this level which can be found by entering a red pipe in the area with Fire Bros. The player enters an area with a Glow Block, along with a Swoop swarm. After that area is the Red Flagpole. This unlocks a Warp Cannon which takes the player to World 8. Players can run through this level with a Mini Mushroom by dashing across the water.