The Wii is not forward-compatible. It cannot read Wii U "WUD" or "WUX" files.
If you want new levels and a fresh experience on your original Wii, the homebrew community has created what is essentially a "sequel" within the Wii's hardware limits. New Super Mario Bros U Wii Roms For Wii-
While the title is a popular search term, it contains a major technical contradiction. New Super Mario Bros. U is a Wii U title, and the original Wii console is not powerful enough to run Wii U games. The Wii is not forward-compatible
To play the genuine New Super Mario Bros. U , you must use one of the following: Is NEWER Super Mario Bros. Wii Actually Good? New Super Mario Bros U Wii Roms For Wii-
