World 12-2 (Super Mario Maker for Nintendo 3DS)
From the Super Mario Wiki
World 12-2 is the second level of World 12 of Super Mario Challenge from Super Mario Maker for Nintendo 3DS.
The level begins with a Super Mushroom inside a ? Block. Once Mario becomes Super Mario, he can break the Brick Blocks. After this, a Fire Koopa Clown Car is used to break Hard Blocks blocking the Warp Pipe. In the subarea, the level autoscrolls. The is no ground below, so the player must use a Fire Koopa Clown Car. Enemies appear throughout the level. They are put in a way so they can interact with the player. For example, Bill Blasters are put on Red Koopa Paratroopas so that they can shoot Bullet Bills, and Goombas and Paragoombas are on a track. There is a Fire Flower surrounded by Hard Blocks, which the player can get. There are individual Red Koopa Troopas on Brick Blocks, which can be used to score a lot of points. Bob-ombs are put on red Koopa Troopas, which are on Brick Blocks; this can help blow up the wall of Brick Blocks. After a certain point, all enemies become big. At the end of the corridor, there is a ? Block with a Super Mushroom on a Fire Flower inside before a Warp Pipe that leads to a fight in the same manner, though with ground, against a Big Winged Bowser in between two Boos, one of which is big. After defeating Bowser, the player receives a Key, which unlocks the Key Door. Through the door, stairs made of Hard Blocks appear before the Goal Pole.