Known Bugs and Glitches

Many video games have glitches, and New Super Mario Bros. Wii is no exception. This article will list known glitches in the game so you can avoid replicating them in your custom levels. There may still be some glitches that are undiscovered and unlisted here. If you find a glitch, feel free to add it to the page! Also, it'd be nice if you have either a video or image of the glitch happening in-game, you can choose whichever represents the glitch best.

=Minor Glitches= These are minor glitches that will cause no harm to the player(s), and have no major impact on the game.

Toad's Water Behavior
If a toad spawned from a Toad Needs Help ? Block is thrown into water, he'll swim infinitely in the direction he's facing (until he exits the water), and cannot be grabbed. Also, something worth noting, however unrelated, if a player holding a Toad jumps into water, they will float at the surface of the water.

This is likely an intentional feature, and not a glitch, however it is worth noting.

Trap Players in a Wall
This glitch requires multiplayer to work. In a cramped space (two tiles tall) with a horizontal pipe, you can take player 2 and throw them up at the 'corner' where the ceiling and pipe meet. Player 2 will get stuck inside the wall. This glitch can be easily done in in retail 5-4 Zone 2.

Frozen Koopa Paratroopa in Log
This glitch requires an Ice Flower or a Penguin Suit. When a frozen Koopa Paratroopa gets frozen in mid-air, it will fall down. However, if there is a log floating on poison below the Koopa Paratroopa, it will not break and instead will enter a weird state where they don't dissolve in poison like other frozen enemies do, cannot be broken with a normal ground-pound, penguin slide, or with a shell, and hides behind the log. You can stand on it.

Micro-Goombas Surrounding Players in Yoshi's Mouth
This glitch requires multiplayer and Yoshi to work. When Micro-Goombas surround a player, for example, Luigi, another player, Mario, can take a Yoshi and put it in Yoshi's mouth. The Micro-Goombas will still surround the player in Yoshi's mouth.

Yoshi's Water Incompatibility
This glitch requires Yoshi, and some water. Jump into the water while on Yoshi, and he'll 'take damage' from the water, and start running. Yoshi is now stuck in the water, and you cannot get back on him unless he exits the water.

= Major Glitches = These glitches have a major impact on the game, such as causing softlocks and crashes.

Yoshi Fruit Glitch
This glitch requires Yoshi, 5 Yoshi Fruits, and an enemy. When Yoshi eats the fifth fruit and gets hit by an enemy on the same frame, the game will crash. This glitch is fixed in NewerSMBW.

Brick Block Softlock (Ground-Pounding the Goal Pole)
This glitch requires a level with brick blocks as terrain in-between the goal flag and fortress. If you ground-pound above the top of the flagpole (must be above the top as you need to trigger the flagpole while ground-pounding), Mario will do his usual 'course clear' animation, but when he walks forward, the brick blocks will turn into used blocks, and Mario will be frozen in his walking animation. An example of this glitch in-game can be found here.