World 4-3 (Super Mario Maker for Nintendo 3DS)
From the Super Mario Wiki
At the start of the level, right above Mario is a ? Block with a Propeller Mushroom. However, this is optional. In the next area, a Bill Blaster shoots out Propeller Mushrooms, which are needed to get higher. Above, there is an eight-Goomba stack and a Key to the next area. On a side note, there are many decorations throughout the level, even in normally unattainable spots. In the next area, another Bill Blaster that shoots Propeller Mushrooms appears. This is used to get past the Brick Blocks and get the Key guarded by the eight-Goomba stack. One-Way Walls are here so that the player can get the mushroom back, but prevent cheating. In the next area, Skewers are present to stop Mario from getting to the top. A Red Bill Blaster that shoots out Propeller Mushrooms can also be found. After going through the Pipe, there is a Bill Blaster shooting Propeller Mushrooms to the left and a Chain Chomp to the right. A huge gap appears, but there are Cloud Blocks that make it smaller. After this is an eight-Goomba Stack followed by a Bill Blaster shooting out Propeller Mushrooms. The player needs to use the Propeller Suit to reach the next high platform, but if failed, the player can try to get to some Cloud Blocks below. Another challenge is for the player to get past three towers with a gap in the middle somewhere, which, if failed, can be retried by a Conveyor Belt going left. After this is an eight-Goomba Stack and a Bill Blaster shooting out Propeller Mushrooms. Two Bumpers appear to help the player reach the pipe at the end. After this, the goal can be reached, but the Propeller Suit is needed to get the top.