WARNING: The following contains spoilers for Season 1 of Shaman King (2021), now streaming on Netflix.
There are quite a few emotional arcs that Season 1 of the Shaman King reboot runs through, honoring what was done in the manga and the previous anime. There's Yoh, finally realizing he has a powerful Asakura legacy to live up to, as well as Anna, who's understanding more about her love for Yoh.
Of course, all of this is layered on top of a bunch of kickass fights and rivalries that act as precursor to the Shaman Fight tournament. Some powerful arcs include Hao's dark destiny and the mysteries behind Silva and the Patch Tribe, which leave us wondering if the folks throwing the competition have good intentions. But while all these intersecting threads are quite inviting, Season 1's best arc has nothing to do with the tournament.
Shaman King's best storyline revolves around the journey of Tao Ren as he tries to unlock his full potential. He's been using Bason, a former warrior in the Kublai Khan era, as the ghost mixing with his Over Soul (life essence), but he gets clouded in his rivalry with Yoh. He wants to defeat Yoh, trying a few times to embarrass the kid but Ren soon discovers he's inferior. He lacks the conviction, heart and soul that Yoh has, evidenced by how the protagonist treats his ghost, Amidamaru and friends as family.
This inspires Ren to treat Bason better, although he realizes he's flying off the handles after killing Chrom in a warm-up event. Ren heads back to China to fight his dad, Yuan, wanting to let go of his rage after years of abuse and being conditioned to be a killer. What makes it even worse is that his sister, Jun, has been imprisoned and beaten by Yuan as she lost to Yoh and tried to get her dad to see the light too. She doesn't want to be a weapon, and Ren shouldn't be one either -- which Yuan doesn't like.
It leads to a flurry of fights in their castle as Ren tries to rescue her, only to get pummeled himself. Luckily, Bason summons Yoh and co. to help out, leading to them fighting the zombies (Jiang Shi) that Yuan reanimated. His legion includes Pyron Lee's master, which makes it more personal for Jun as she didn't want to use Pyron as a pawn and WMD anymore. It culminates in Ren fighting his father's giant form, but finally understanding this was all an Over Soul projection too. As such, he's able to beat Yuan, with his mom and grandfather then intervening.
They want their inner turmoil to stop because this civil war has taught them the importance of family. It's changed Ren too, making him and Jun forces for good while paving the path for Yuan to eke out a second chance. And make no mistake, just like the Uchihas in Naruto, there's a lot to atone for before redemption can be earned in Shaman King -- but it's all about breaking those vicious cycles and protecting the next generation.
Seeing Ren's friends risking their lives for him makes the Tao clan proud, while the youngsters also become closer as they unite. It strengthens them for whatever is to come, whether it's random fights or the competition itself, with Ren's clan accepting that being powerful doesn't mean someone is strong or virtuous. This reminds the teens, even if they have to clash with each other, they can still count on each other as family when it's said and done. It's a powerful threat that serves as inadvertent prep, adding nuance to Yoh, Ren and co. as it evolves and matures them for what's to come.