Second Course (Platform Panic Pack)
From the Super Mario Wiki
The level begins with a few synchronized Snake Blocks and a few Goombas and Paragoombas. After a while, a Boomerang Bro appears, followed by the Checkpoint Flag and more synchronized Snake Blocks with Goombas. After a while, a Snake Block staircase appears with a Boomerang Bro beneath it, along with the Goal Pole.