Ever since King’s introduction I have wondered how Kaido came across him. How did the two meet and was King the only Lunarian member Kaido encountered? When Yamato was introduced, I wondered if Yamato’s mother was part of the same race as King. There isn’t anything definitive to suggest so but with every chapter than elapses with Yamato’s mother omitted, I grow ever curious wondering if her role within the story is being saved for a major reveal. If there was a faction that would have another Lunarian member existing within it, it would be the Beast Pirates. King is likely not the sole survivor of the race. Yamato’s mother may not be important or she may be incredibly important. What is certain is that there existed a person intimate with Kaido and Yamato that existed. She does not have to be mentioned for the audience to be aware that Yamato had a mother and Kaido a partner. The foreshadowing exist naturally with the potential to track forward in a myriad of directions.
If Yamato’s mother was from the Lunarian race, it would make Yamato half Lunarian. Looking at King for racial features, the Lunarian people possess the ability to burst into flames and have wings. King is covered up so at present it is hard to ascertain the facial and skin features of the Lunarian race. Yamato does not hold any of those features. But does this mean he is definitely not part Lunarian? Certainly not but it does dampen the possibility. Yamato being half-Lunarian could explain the lack of racial features. What has me interested is how Yamato has been fighting with Kaido for two decades and has yet to receive a noticeable scar such as a burn. Kaido is able to transform into a Dragon and part of his attack rotation is his Blast Breath – an attack where he fire a blast of flame breath at the target. One can imagine how many times Yamato would have been subject to Kaido’s blast breath and yet there are no burn marks so to speak of, why? What happens if while Yamato didn’t manifest the ability to burst into flames, his Lunarian blood still provided him with a natural resistance to fire. Such a potential could explain how Yamato has been able to fight fire-element opponents such as Ace and Kaido without receiving any burns.
Taking this theory further, only after transforming into his Mythical Beast Form is Yamato able to access more of his Lunarian abilities. Through the Okuchi no Makami form, Yamato gains the ability to use fire based attacks. An attack that blends both the frost nature of the Inu Inu no Mi, Model: Okuchi no Makami and the Lunarian ability to generate flames. This could be how Yamato is able to counter Kaido’s Blast Breath with his Namuji Glacier Fang, which appears to be a frost flame-based breath attack.
The race name Lunarian suggest a connection to the Moon and their presence atop the Red Line in the past provides the basis for surmising their conflict with the Tenryuubito. If Yamato is to be focused on beyond Wano Kuni, the story surrounding the race of Kaido and Yamato’s mother can be featured as a driving force behind what he ends up doing after the events in Wano Kuni. The Tenryuubito appears to be enemies of the Lunarian people and with the Tenryuubito coming into focus as the upcoming antagonist, it does set a character up with connections to the Lunarian people quite nicely.
The relevance of Yamato’s mother may or may not be significant in the overall story of One Piece but just as how Oden learned about the Kozuki history through his journey across the Grand Line with Whitebeard and Roger, Yamato will learn about the history of his blood (the race or races he belongs to) through the journey with the Straw Hat Pirates. Focusing just on Kaido, he isn’t just some human. He does not merely have horns. There is story behind his blood and the reason why he too is interested in Joy Boy. Kaido didn’t stumble upon Wano Kuni but specifically chose it. Oda-sensei has set-up the story of Yamato to extend beyond his admiration of Oden and the goals Oden held. The dream Yamato holds which Oda-sensei has reiterated several times across the arc is testament to the independence Yamato has to Oden’s story. Yamato will carry on Oden’s will and see it through but at the same time, he will follow his own desires and path before him.