The following contains spoilers for Thor: Love and Thunder, now playing in theaters.
Thor: Love and Thunder introduced the driven yet utterly terrifying villain, Gorr the God Butcher. Though he was only a man, he carried with him the Necrosword, a weapon that could access the Shadow Realm and gave him the power to kill Gods at the cost of his humanity. But because of the changes the Necrosword went through on its way to the big screen, mysteries remain about its origin and uses. However, the biggest question may have already received an answer.
In the comics, the Necrosword got created by Knull, King in Black and God of the Symbiotes. However, he lost it in a battle, and the sword wound up with Gorr, who, like in the film, lost his family and swore vengeance against the Gods. But because symbiotes strictly belong to Sony Pictures, it was imperative that the Necrosword still be devastating without tying to Spider-Man. What came to light was that the sword was part of the Shadow Realm and corrupted its user like an infection. And while it hasn't come out who the other user was before Gorr, a New Rockstars video may have provided an answer.
At the start of Love and Thunder, Gorr, after losing his daughter to starvation, was called to an oasis where he found the Necrosword. He stumbled after he fell over the corpse of another alien being that got covered all in black. And according to the theory, because the sword has ties to the Shadow Realm, the being that died could be the ruler of that domain, Kaa.
Kaa was a little-known character that debuted in Strange Tales #79 by Stan Lee and Jack Kirby. He was the ruler of the realm and appeared in future Marvel issues facing off against other heroes in a battle for Earth. If this being was Kaa, it could also explain even more lore on the Necrosword. Since it was centuries old, it likely changed hands many times, and once it reached Kaa, he had wielded it for so long that the corruption took over completely, as it almost did for Gorr. That would've made him one of the oldest living owners of the blade and likely so corrupted he was as brutal as the creatures he could conjure.
But if Kaa ruled the Shadow Realm, that would imply that other rulers came before him, as he likely didn't live as long as the sword. If true, that would mean the weapon operated on its own rules, not tied to the books. Therefore, those who possessed it would become the new rulers of the Shadow Realm and gain its power. While Gorr had the drive, the sword gave him the strength and resources to combat his enemies and seek the revenge he wanted. Plus, as a blade designed to slay Gods, it had to rule over the shadows to give the wielder a way to overpower its targets.
For now, it's unclear whether the dead body behind Gorr was Kaa in Love and Thunder. But if so, it would make for a great Easter egg for die-hard Marvel fans and offer a unique addition to the overall lore of the Marvel Cinematic Universe. Furthermore, it adds more story to the Necrosword that explains its abilities better without completely removing the mystery behind it. While this may be the end for the sword, its history and demise helped open even more doors for more characters from Marvel's past to appear in live-action.
To see Gorr's predecessor, Thor: Love and Thunder is now playing in theaters.