u/Keundt

Episode count concept - 8 episodes per season - 9 seasons by current anime arc

Season Episodes Arc
Season 4 3 Episodes Jaya / Warlord Meeting
5 Episodes Skypiea
Season 5 1 Episode Long Ring Long Land
3 Episodes Water Seven
3 Episodes Enies Lobby
1 Episode Post-Enies Lobby
Season 6 2 Episodes Thriller Bark
2 Episodes Sabaody Archipelago
2 Episodes Amazon Lily / Straw Hats
2 Episodes Impel Down
Theatrical Release 2hr Movie Marineford / Post-War
Season 7 1 Episode Return to Sabaody
2 Episodes Fishman Island
2 Episodes Punk Hazard
3 Episodes Dressrosa
Season 8 1 Episode Zou / Kaido Intro
2 Episodes Whole Cake Island
1 Episode Reverie
1 Episode Warlord Hunt / Wano: Act 1
1 Episode Wano: Act 2
1 Episode Wano: Backstory
1hr30 Movie-Length Wano: Act 3 / Lulusia
Season 9 3 Episodes Egghead / Side Stories
? Episodes Elbaf

Notes:

  • Marineford turned into a theatrical release. I feel that this would be a necessary decision to keep the eight-episode count for surrounding events. It also just makes sense for Marineford to be a movie.
  • I moved the warlord hunt to Wano Act 1 so the episode can open with Koby being captured by an Emperor and end with Luffy being captured by an Emperor. It also shows that the World Government doesn't waste any time after the Reverie.
  • I moved Lulusia to the end of Wano so that the post-Reverie events conclude in the same season, and the season ends with a massive cliffhanger.
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u/Keundt — 12 hours ago