WARNING: The following contains spoilers for Godzilla vs. Kong, now in theaters and on HBO Max.
In Legendary's MonsterVerse, Kong: Skull Island blew the lid off the existence of the behemoths known as Titans. It smartly expanded on 2014's Godzilla, providing some context and history of where the monsters came from, where they ended up living and clues on how they moved around the planet. We discovered Kong and creatures like the Skullcrawlers were tied to the Hollow Earth theory, which stated there was a world within worlds at the center of the planet -- a land lost to time.
With Hollow Earth all set up, this left fans wondering how Skull Island would factor into Godzilla vs. Kong. Some thought the two giants might brawl on the island, while others suspected Kong's home would be destroyed, causing him to seek revenge on the outside. Ultimately, while both Titans didn't really have an impact, Skull Island's fate is still a depressing one.
Early in Godzilla vs. Kong, former Monarch scientist Dr. Nathan Lind tells Apex Cybernetics Skull Island is an extension of Hollow Earth. It's basically Hollow Earth on the surface, connecting to Dr. Houston Brooks' theory from Skull Island and the revelation about Godzilla's underwater tunnels from King of the Monsters. But after King of the Monsters, Skull Island isn't stable. This happened when Titans went to the island after Godzilla killed Ghidorah and became the alpha.
It's never fully explained, but it's hinted the active Titans died out, except for Kong. As for the state of Skull Island, Monarch builds a dome around it, calling it "Outpost 236," where they maintain a suitable habitat for Kong. It blocks out the outside elements, which is now a constant thunderstorm and possible side-effect of destabilization.
The fact Monarch is able to build around the island and study Kong for 10 years without being attacked by other creatures suggests an extinction took place. However, these details are never confirmed, leaving room for a sequel to dissect. While Kong remains in Hollow Earth, monitored by Monarch once again, he could always use a tunnel and return to Skull Island again, which seems to be what the Skullcrawlers and M.U.T.O.s did in the past. However, whether Skull Island remains permanently destabilized, is not entirely clear by the end of Godzilla vs. Kong.
Directed by Adam Wingard and written by Eric Pearson and Max Borenstein, Godzilla vs. Kong stars Alexander Skarsgard, Millie Bobby Brown, Rebecca Hall and Brian Tyree Henry. The film is in theaters and on HBO Max now.