Toady-Toad Island is the 13th level of Super Releasio 64 and its variants. It is said to be unlucky.
It is a floating island. Unlike Toad's Fortress (which is also in midair) it is not constantly falling. Some sort of gravity-defying force is keeping it in midair. It has several warp pipes, which will either shrink or enlarge the one who entered them. In addition to the size change, it also teleports the one who went into the pipe to a Parallel Universe of the course, but in a different size. One of these has everything tiny, and the other huge.
It is in Toad Hell.