Anguirus existed in the MonsterVerse, but died thousands of years ago. A skeleton that looks identical to the Toho kaiju appeared in a brief scene in Godzilla: King of the Monsters. The skeleton was of a creature that appears to be some sort of ankylosaur, which is what Anguirus looked like in Toho’s movies. Of course, one might say that it may just be a giant ankylosaur, and not Anguirus himself. But, it has a spiked nose that differentiates it from that species and more closely aligns it with the Toho kaiju.
The connection to Anguirus was hinted at by Godzilla: King of the Monsters director Mike Dougherty. On Twitter, Dougherty was asked by a fan about Easter eggs to watch out for, prompting him to mention a “skeleton that may or may not belong to Anguirus”. No one involved with the movie, including Dougherty, has outright stated that the skeleton belongs to him, but the reason for that isn’t hard to decipher. Since Legendary Pictures doesn’t have the rights to him, the movie can do nothing more than imply or suggest that the skeleton is his. At this current juncture, Anguirus can’t be officially added to the MonsterVerse. For now, the only Toho kaiju that are confirmed to exist in the MonsterVerse is Godzilla, Rodan, King Ghidorah, and Mothra, with Mechagodzilla presumably becoming the fifth kaiju from Toho’s library to be adapted in Godzilla vs. Kong.
For now, Anguirus’ skeleton remains as just a fun Toho Easter egg. However, that hasn’t stopped viewers from speculating about him. Numerous questions are being asked the monster. What was his role in the MonsterVerse, what was his relationship with Godzilla (if he had one at all), what was he doing in Godzilla’s home in the first place, and how did he die?
Anguirus’ skeleton was spotted in the scene where Godzilla’s underwater city was destroyed by the nuke. It being down there doesn’t confirm that he was a resident of this place, but it does make it a strong possibility. It’s known that Godzilla was worshipped by the people who dwelled there, but he may not have been their only god. The redacted text in the Godzilla: King of the Monsters credits makes it clear that Godzilla wasn’t the only Titan that humans had a positive, symbiotic relationship with. It was said that humans lived near Titans for protection. Anguirus could easily have been one of them, and was living in peace within this ancient civilization.
Based on what Legendary has done with Godzilla, Rodan, Ghidorah, and Mothra, it’s become apparent that the MonsterVerse is going to great lengths to remain faithful to these monsters’ Toho counterparts. If it’s treating Anguirus in the same way, there’s a good chance that his role in the MonsterVerse wasn’t that much different from the one that he had in the Showa series of Godzilla movies. During those years, Anguirus was depicted as a close ally of Godzilla. He was one of a handful of monsters to contribute to Ghidorah’s defeat in Destroy All Monsters, and in Godzilla vs. Gigan, the two traveled together and teamed up to beat the alien duo of Ghidorah and Gigan.
Godzilla’s interactions with Mothra in King of the Monsters and the Titans bowing down to him indicate that Titans are capable of getting along with each other in the MonsterVerse, so it could be that Godzilla and Anguirus were able to coexist in their home. If this was the case, they may even have been allies who helped defend the city from outside threats, such as aggressive Titans who tried to attack it.
A key reveal from the redacted text is that humanity’s relationship with Titans didn’t stay peaceful for long. Apparently, greed and ambition got the best of the humans, leading them to take advantage of the Titans’ size and raw power. Their connection to each other – which may have formed by music – eventually grew into something else. Somehow, the humans figured out that they could control the Titans and started to enslave them. When they began using Titans as weapons, some took issue with this treatment and rebelled. As a result, a human-Titan war broke out that gave rise to a “massive cataclysm”.
One thing that the redacted text doesn’t explain is how this war was waged. Without advanced technology, the humans lacked an obvious way of fighting back unless they maintained their control over some of the Titans. It could be that the Titans fought each other, and this massive gathering of colossal beasts fighting it out is what led Godzilla’s city to ruin and other geological catastrophes around the world. Anguirus may have been killed by these events, or he could have met his end before all of that. It could be that he was a willing (or unwilling) participant in the war. If it’s true that he fought in the war, he could have sustained critical injuries in combat against opposing Titans before succumbing to his wounds.
Anguirus is dead, but if Legendary does acquire the rights at some point in the future, there are two different ways he could be properly explored. One way is through flashbacks that revisit ancient times. King of the Monsters created a lot of interest in Godzilla’s past, so going back to those days may be something that a later movie will look to do. The second way is for the MonsterVerse is to introduce a second member of Anguirus’ species.
As noted by Dougherty, other Toho monsters could easily be discovered by Monarch in the years to come, so even though he hasn’t been seen or mentioned yet, he could still be out there somewhere, possibly deep within the tunnels of the Hollow Earth. If Legendary has acquired the rights to the monster in secret, a surprise Anguirus appearance in Godzilla vs. Kong would feel like a perfect fit for the film. As a Titan with a connection to their ancient history, it would make sense for him to be officially revealed at a time when Monarch is exploring Hollow Earth and investigating the Titans’ origins. Regardless of when this happens, Angurius’ MonsterVerse introduction would give Godzilla a reliable ally going forward.