The fourth filler arc in Bleach is the Gotei 13 Invading Army arc. This arc occurs after the Soul Society arc and follows the story of a group of mysterious warriors who invade the Soul Society. The arc introduces new characters and challenges for the main protagonists to overcome. While not part of the original manga storyline, the Gotei 13 Invading Army arc provides additional content for fans of the series. **

Opinions on the first Naruto Shippuden filler arc vary among fans. Some viewers enjoy the arc for its character development and world-building, while others find it slow-paced and lacking in comparison to the main storyline. Ultimately, whether the arc is considered good or not depends on individual preferences and expectations. **

The filler arc in Bleach begins in episode 168, titled "The New Captain Appears! His Name is Shusuke Amagai." This arc deviates from the original manga storyline and introduces a new character, Shusuke Amagai, who becomes the new captain of the 3rd Division. The filler arc spans from episode 168 to episode 189, before returning to the main storyline. **

After the Sabaody Archipelago arc, the next arc in the One Piece anime without filler is the Amazon Lily arc. In this arc, Luffy arrives at the island of Amazon Lily, which is inhabited only by women. He encounters the fierce warrior tribe known as the Kuja and eventually meets their leader, Boa Hancock. This arc sets the stage for Luffy's journey to rescue his brother Ace from Impel Down and eventually Marineford. **

The first filler arc of Naruto Shippuden is the "Kazekage Rescue Mission" arc, which starts from episode 1 and lasts until episode 32. This arc focuses on Team Kakashi's mission to rescue Gaara, the Kazekage of the Hidden Sand Village, who has been kidnapped by the criminal organization Akatsuki. During this arc, viewers are introduced to new characters and storylines that are not part of the original manga. **

Mitsuki's arc in the Boruto series is made up of filler because the anime has caught up to the manga and needs to create original content to give the manga time to progress. This allows the anime to continue airing without having to go on hiatus. Additionally, filler arcs can also be used to further develop characters and explore side stories that may not be present in the original manga. This can help to provide more depth and background to characters like Mitsuki, adding to the overall richness of the series. **

In my opinion, the best Bleach arc was the Soul Society arc. It was the arc that really hooked me into the series with its intense battles, intriguing plot twists, and the introduction of memorable characters like the Captains and Lieutenants of the Gotei 13. As for the best filler arc, I would say the Zanpakuto Rebellion arc. It was a fun and creative arc that delved into the inner world of the Zanpakuto spirits, providing some entertaining and unique storylines that added depth to the Bleach universe. **

Mitsuki's arc in the Boruto anime is made up of filler episodes because it diverges from the original manga storyline. The anime creators likely wanted to explore Mitsuki's character and background in more depth, which led to the creation of these filler episodes. Additionally, filler episodes can help to slow down the pacing of the anime and allow for more character development and world-building. **