Walkthrough: In this Broodal Fight, you will battle the Blue Broodal once again. He'll begin much like the last time you faced him, shooting poison all around the arena at you. Simply by knocking off his hat will leave him vulnerable, thus giving Mario and opening to jump on his noggin. After being hit, he'll retreat into hit hat like last time, spinning around and sending poison virtually everywhere. When he does, use Cappy to knock him back, thus stopping him from spreading anymore poisonous goop.
When he lands, he'll launch another wave of poison throughout the arena. After avoiding this, do the same as before and knock off his hat to land a jump to the head. After you do, he will literally do the exact same thing as before. Repeat the process one more time around, defeating the Broodal for good with one more blow to the head. After defeating him, you will only receive a Power Moon.