At the end of the path, collect the Super Mushroom in the box above and enter the Green Pipe to face the boss. To defeat this easy boss, stand away from him until he spins his arms. This will make him dizzy, when he’s dizzy jump on his head or Tanooki tail him. Then avoid his shell. Mix and repeat. If you have a fire flower, you can keep shooting him until he retracts into his shell. Note that he will spin for a longer period after hitting him twice. After being the boss, enter the Green Pipe.