In Tiny-Huge Island, there is a cave with eight red coins, a windy valley known as Windswept Valley where Mario can race Koopa the Quick again. Depending on the level's current size, Mario can change the level to the opposite size, big or small when he goes down a Warp Pipe. There is even a giant portrait in plain sight when the door to the stage is entered, or a small portrait to the left. The corresponding painting sizes affect the level's size. The size even affects most of the enemies. There is also a Bubba in the area which has the ability to swallow Mario to make him lose a life. If Mario smashes the top of the mountain when the island is small, he can access Wiggler when the island turns big. Some of the entrances can only be accessed when the stage is big.
Tiny-Huge Island is similar to several other stages in the Mario series. In Super Mario Bros. 3, for example, there's an entire world where the enemies and objects are much larger than they normally are named Big Island. The Supermassive Galaxy in Super Mario Galaxy 2, which was released several years after Super Mario 64, is similar to Tiny-Huge Island because everything is sized the same was as in Super Mario Bros. 3's world.