World 4-4 (New Super Mario Bros. 2)
From the Super Mario Wiki
World 4-4 is the fourth regular level of World 4 in New Super Mario Bros. 2. It is unlocked by beating World 4-3, and unlocks World 4-5 upon completion. It is an aerial containing many tilting Mushroom Platforms.
Mario begins on a stationary mushroom platform which is covered in snow. The first tilting platform can be found with a ? Block above it containing a Super Leaf. Goombas and Koopa Troopas can be found, followed by a small piece of land. Going across the next tilting platform are several yellow platforms that act like balances and will drop when one side is weighed down too much. This is followed by another piece of land where more Koopas and Koopa Paratroopas can be found. Going up several tilting platforms will bring Mario to a Gold Ring where a single Koopa sits on a higher platform while Goombas can be found on the lower platforms. A ? Block with a Super Leaf can be found, along with the checkpoint on hilly ground. More tilting mushroom platforms can be found, along with a Red Ring. This follows with more balancing platforms where Mario needs to make his way upwards. More Goombas and Koopas can be found along with these platforms, which is immediately followed by the flagpole.