is one piece episode 356 filler?

With the Straw Hats split up, Luffy's party runs down a corridor with Luffy assuring Zoro's party would be fine as he is determined to get Moria. Chopper informs if they keep going, they would be in the freezer.

Suddenly, they run into Hogback and Cindry. Chopper volunteers to take on Hogback while Luffy goes ahead, but Cindry throws plates at the captain.

Robin uses three arms to grab the maid zombie's arm preventing her from throwing more plates at her captain. Robin also stays behind to fight.

Chopper accuses Hogback of being a mad scientist who admires how he escaped the garden.