World 4-Airship (New Super Mario Bros. Wii)
From the Super Mario Wiki
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The main enemies in this level are the Mechakoopas and the Burners. Near the end, there are Cannons and pipes that release Bob-ombs. The flames from the Burners can make them explode. The boss of the airship is Bowser Jr. in his Junior Clown Car. The player must propel up with Propeller Blocks, or a Propeller Suit, and stomp on his head three times. The Propeller Blocks can also be utilized as weapons, dealing damage equal to a single stomp when thrown at Bowser Jr. After Bowser Jr. is defeated, Magikoopa flies up with Bowser Jr. They then eject Mario and gang from the Airship, which flies away, forcing Mario to chase it to World 5.