season 4 spoilers

he senses the presence of Upper Rank Five, Gyokko. Muichiro attacks him, but Gyokko moves to different pots and avoids his slashes. He summons more fish Demons that send an array of needles towards Kozo and Kotetsu, but Muichiro shields them

Gyokko reveals the needles are poisonous and berates Muichiro, resulting in another sudden memory recurring to him.

He tries to attack Gyokko, but gets trapped in his Blood Demon Art: Water Prison Pot