From the Super Mario Wiki
Mushroom Hills is Mini Toad's world and the sixth overall world in Mini Mario & Friends: amiibo Challenge. The main mechanic featured in this world are Mushroom Trampolines that bounce Mini Toad into the opposite direction when tapped with the stylus. They can be found both vertically and horizontally. Mini Toad's special ability in this world is the Small Crawl, which allows Mini Toad to fit underneath narrow passages that are inaccessible to the other Minis. One main level also takes place before this world, Level 7.
The background in this world is styled similarly to Super Mario 3D Land and features several mushrooms as well as a red Toad House. The background music featured in this world is a cover of the Winding Ravine theme from Mario vs. Donkey Kong: Tipping Stars.