Super Mario 3D World: 6-A -- Prince Bully Blockade
Prince Bully is a Bully in silver armor. There's only one of him to defeat. There are several clear pipes in the wall drawing air out of the room. Push Prince Bully to a pipe and he'll get stuck. Push him again and he'll go through the pipe and come out a different one. He'll be cylindrical in shape. Stomp him for a hit before he gets back up. Do this three times to defeat him and get the Green Star.