is one piece episode 346 filler?

The Straw Hats are beginning to wonder where Sanji and Zoro are. A golden knight begins walking towards Luffy's party with a Straw Hat and falls over.

It is Luffy in disguise. Franky then tells of how his heart became black.

Buhichuck then brings Luffy's party to a room full of tents. Then a knight dives down to hit Franky who dodges.

It is a General Zombie. This knighted zombie fights with Franky and is unable to pierce him.

The knight launches a cross-shaped projectile that can cut steel. The cyborg then shoots a Weapons Left at the knight.