World 6 is the 6th world in New Super Mario Bros. Wii. It is a mountainous place. Many Bullet Bills appear in this world. World 6 is a sunny level, but not as bright as World 4 (NSMB Wii) or World 1 (NSMB Wii) because it is in the mountains. Morton Koopa Jr. is fought twice here. There are 7 levels here plus 3 Mushroom Houses, the Enemy Course and the Ship. World 6-5 is an underwater level. It features Porcu-Puffers. World 6-6 is a dark cavern. You must ride on the boat with a light while avoiding the Piranha Plants, Cheep-Cheeps, Swoopers and Fire Bros. The light of the boat can be controlled by tilting the Wii Remote. Bowser Jr. is fought in a clown copter in the Ship. You must take the other clown copter and knock Bowser Jr's copter into the electric fence.
This level features several ledges that Mario must hang from, and rocky walls that must be climbed. There are a lot of Bullet Bills and Stone Spikes in this level.
This level is an underground level that has many rotating circular platforms in it. The main enemies are Spinies and Swoopers. There are also some Piranha Plants, and at the end of the cave, there are two Sledge Bros.
In this level, there are many Super Piranha Plants, as well as Stalking Piranha Plants and Buzzy Beetles. This level is an underground area with rising and lowering platforms, which Super Piranha Plants are on top of. When the player sees a passageway blocked with Bricks, he can break them and Wall-Jump to get a Star Coin. Some Question Switches can be jumped on top of to raise or lower the water level.
This tower has two spiked pillars that the player must avoid. There are also some Pipe Cannons and moving platforms that the player must use to proceed. At the very top, the player will face Morton Koopa Jr. During the battle, the player must avoid two spiked pillars which strike the sides of the stage.
This level features Porcu-Puffers, tides, and large Question Blocks. There's a secret exit that takes the player directly to the castle of World 6 (NSMB Wii).
This level takes place in a very dark, underground cavern. There's a boat with a light that the player can rotate using the Wii Remote. Various enemies such as Piranha Plants, Cheep-Cheeps, Swoopers, and Fire Bros., appear in this level. A secret exit exists in this level. It can be found by entering a red Warp Pipe in the area that is infested with Fire Bros. The player will be in an area with a Glow Block, and a Swooper infestation. After that, is the secret Flagpole. The Cannon takes the player to World 8.
In this level, there are Spiked Balls and Giant Spiked Balls which can hurt the player. Of course, they can also destroy the many Dry Bones in this level. This level is set above a pool of lava with moving platforms. The castle features two areas, the second area being infested with Spiked Balls. The player, once again, faces Morton Koopa Jr. At times, he will pound the ground, causing two pillars to rise from the ground.
This level has Rocky Wrenches, which appear for their first time, and the Hero Car, which also appears for the first time. This is where the player fights Bowser Jr. for the second time. Other dangerous things are wheels, which the player must jump on to proceed. In Bowser Jr.'s fight the player must climb onto his Koopa Clown Car (known as the Hero Car) and knock Bowser Jr. into the electric fence.
Added by Smashbro8
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