Revenge is a Dish Best Served Cold with Shitake Mushroom Sauce. - S1.E30

Just when the fight for King of Wiggin Specialist was finished, a big-mouth ninja assassin arrives to challenge Bo-bobo to take on his master, the horrific OVER of the Baldy-Bald Big Four! After Bo-bobo and the others can get past his bone-headed ninja tricks, he sends them to the entrance with a flying duck-loving warrior to face. (and Serviceman hanging by a limb) And beyond that is a force of The Ultimate Five Assassins to get past along the way, the first of which is...a playful little girl!?