Before the official One Piece manga debuted, Oda released a few one-shot series, one of which was called Monsters. Oda created Monsters in 1994, the series tells the story of Ryuma Shimotsuki, who lived about 400 years ago and is a legend in the land of Wano.
The anime, directed by Sunghoo Park, director of Jujutsu Kaisen season 1, has already debuted on Netflix. However, in a recent interview, Oda talked about why he agreed to adapt the Monsters anime, titled Monsters: Ippaku Sanjō Hiryū Jigoku.
According to a famous One Piece translator, Oda said:
“I thought, ‘I guess this is fine.’ Actually, before this adaptation happened, over ten years ago, was it at Jump Festa or Anime Tour? There was an offer to animate Monsters. But I turned it down at that time.
I think it would be fun to show something that I created when I was young to the audience who are looking forward to One Piece. Speaking of personal experience, I went to Toriyama (Akira) sensei's anime tour a long time ago, and I was happy to see that one of Toriyama sensei's previous one-shot stories was adapted into an anime.
At the time, I couldn't imagine One Piece fans would be as excited about Monsters as they were. Now, anime adaptation talks are back on. The Wano Country arc is complete and the story's connection to Thriller Bark has been established.
I thought it would be good as a side story to One Piece, so I said yes. I just gave the green light, but I didn't really explain the connection to One Piece to them. On the storyboard they sent me, Zoro appears at the end, and I thought, 'Yeah, that's perfect.'”
Monsters is also Eiichiro Oda's first work to be adapted into an anime since One Piece. And if you don't know, the name “Ippaku Sanjō Hiryū Jigoku” is the Japanese name of a technique that Zoro used to defeat King in chapter 1062.