is one piece episode 13 filler?

The children attempt to enter Kaya's mansion to check on her, but Usopp's secret entrance had been sealed and they cannot climb the gates. Inside the mansion, Kaya exits her bedroom to find a wounded Merry on the floor.

Merry reveals that Usopp had been telling the truth and Klahadore was indeed a pirate attempting to assassinate Kaya for her family fortune. As the invading Black Cat Pirates find themselves unable to fight off Luffy and Zoro, Jango hypnotizes them to increase their strength.

The newly hypnotized combatants become far stronger, shattering cliffs with a single punch.