WARNING: The following contains spoilers for One Piece Chapter #1022, "The Stars Take the Stage," by Eiichiro Oda, Stephen Paul and Vanessa Satone, available in English via Manga Plus and Viz Media.
Marco not only made a glorious return to battle in Chapter #1022 of One Piece, but he also hinted at the origin of one of the All-Stars. While we can't see what he looks like under his black garb, King's abilities have given Marco insight as to where he might be from. Big Mom also recognized his race when she first met him. So, which race is it?
After blocking an attack from King and protecting a recuperating Zoro in the chapter, Marco comments on a legend he heard about "a race of people atop the Red Wall who could burst into flames." He then calls King by his title of The Wild-Fire, seemingly making the connection between the two. While King neither confirms nor denies this connection, it's clear that he is a part of this race, at least to Marco. Although this race is mostly unknown, we've been given hints about it since King's introduction. Big Mom has said that three races were missing from her country, Totto Land. She is amazed to see King, as his race was thought to have gone extinct.
Perhaps we can look to Japanese lore to try and guess what this race of people could be like. Several of the Beast Pirates and their affiliates have origins in Japanese yokai lore, such as Black Maria. The same might hold true for King. We know that the black wings on his back are part of his natural physiology, that he is a "torture-loving pervert," and he can create and manipulate fire. While he initially may be mistaken for a member of the race Tenguyama is from, this most likely isn't the case. Instead, he could be from a race based on the Onmaraki.
Onmaraki are black, crane-like yokai with human-like faces that are birthed from the negative energy of corpses that didn't receive proper funerals. These demons can breathe fire and tend to be found around temples. They have eyes that shine brightly in the night like lanterns, and they like to harass anyone not performing their priestly duties. King has an attack called "Andon," which is a traditional type of lantern that's made up of an oil lamp with a paper-covered wooden stand. VIZ translates this attack as "Imperial Flame." Part of the name "Onmaraki" can be connected to the word "onmyo," which is the idea of yin and yang. "On" in this case can represent the unseen, the hidden, and secret things, usually in a hidden world or the shadows.
While we only have a few things to go on, we can have fun speculating what the race King belongs to are like until Oda decides to give us more information. King could be based on a tengu, an Onmaraki or some other type of creature. Marco and Big Mom recognize them, but until someone comes out and says explicitly what his race is, fans are left to theorize and speculate. With a world as large as One Piece's, anything is possible.
