Giant-sized sequel Godzilla: King of the Monsters will see Titans clash once - and we have a theory about the identity of one of the movie's mystery monsters. The stars of the show this time around are Godzilla himself, Mothra, Rodan, and the terrifying King Ghidorah, all of whom have been heavily featured in the trailers and on their own individual posters. However, the second trailer also offered a glimpse of two Titans who don't look like any of the main four.

King of the Monsters is the sequel to 2014's Godzilla, which kicked off Legendary Entertainment's MonsterVerse, introduced the massive new version of the familiar giant lizard, and pitted him against two MUTOs (Massive Unidentified Terrestrial Organisms). Those two were a male and female of the same species, and were never officially given names besides "MUTO 1" and "MUTO 2."

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MUTO 1 and MUTO 2 weren't the only kaiju designs thrown around for Godzilla, and with the MonsterVerse growing bigger, we wouldn't be surprised if some of those early designs made a comeback. Looking at a shot in the trailer, it seems as though one of them may already have.

Godzilla: King of the Monsters Has Two Secret Titans

Godzilla King of the Monsters Mystery Titans

The four known Titans in Godzilla: King of the Monsters are all pretty recognizable: Godzilla with his upright posture and distinctive back spines, Mothra with her luminescent wings, Rodan with his flame-edged wings, and King Ghidorah with his three heads. Though the latter three were dormant during the first movie, we also know where they're located: Mothra is in a hidden rainforest temple in China, Rodan is inside a volcano in Mexico, and Ghidorah is frozen in the Antarctic. However, in the second full-length trailer for King of the Monsters we see two Titans emerging that don't match any of those physical attributes or locations.

One is a creature with crab-like legs, tunnelling up from beneath an oil field, which looks like it may well be the spider kaiju Kumonga. The other is harder to see, but it is large enough that a mountain appears to have formed on top of it and it looks like it has a hard shell with spines. This Titan looks like it could be Anguirus, one of the very first kaiju featured in Toho's films, which made its debut in 1955's Godzilla Raids Again. However, a recent TV spot offered a better look at both of the mystery Titans, and the one emerging from the mountain could actually be something new entirely.

Theory: The Mountain Monster Is Rokmutul

Godzilla Rokmutul Concept Art

In addition to the two MUTOs, there were several other original kaiju designs created for Godzilla. One was a strange creature with many legs seen destroying a ship in the 2012 Comic-Con teaser, and concept artist Josh Nizzi also shared designs for two creatures that he worked on: a Pterodactyl-esque kaiju, and a six-legged lizard called Rokmutul (pictured above, on the right). Like Anguirus, Rokmutul appears to be largely based on the armored dinosaur Ankylosaurus. However, whereas Anguirus has a hard shell with many closely-grouped, upward-pointing spines (kind of like a cross between a tortoise and a hedgehog), Rokmutul's spines grow directly from its back and are slanted backwards.

Although Rokmutul didn't end up appearing in Godzilla, the movie did establish that there are dozens - possibly even hundreds - of Titans lying dormant underneath the Earth, and it wouldn't be at all surprising if Legendary decided not to let those early designs go to waste. If the mystery Titan in Godzilla: King of the Monsters is actually Rokmutul rather than Anguirus, it would bode well for the future of the MonsterVerse.

Page 2: Why the MonsterVerse Needs More Original Titans

Godzilla MUTOs

What Rokmutul Could Mean For The MonsterVerse

Godzilla: King of the Monsters promises to deliver plenty of fan service for those who were fans of Godzilla before he swam his way over from Japan to the United States. The Toho films have a large gallery of classic kaiju, some of whom will be returning in King of the Monsters, while others wait in the wings as the MonsterVerse continues to develop. However, the MUTOs were one of the most interesting elements of Godzilla because no one - not even the fans - knew exactly what they were. The reveal that of the second MUTO was a major moment in the film, and the fact that they were a mated pair lended some pathos to their deaths.

Kong: Skull Island was also a mix of the familiar and the new. There was King Kong, of course, at the center of the story, but the film also introduced a delightful array of monsters sharing the island with Kong - from the grisly reveal of Mother Longlegs, to the lethal Leafwings, and of course the creepy two-legged Skullcrawlers that plague Kong's existence on the island. Once again, it seems that Legendary isn't just interested in using the MonsterVerse to exhaust the collection of pre-existing monsters that the studio has the rights to, but also wants to build up its own collection of original creatures.

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If Rokmutul (and perhaps also the crab-legged kaiju) are also entirely new monsters, it would prove a continued commitment to fleshing out the MonsterVerse with new designs. After all, King of the Monsters already has four of the most famous kaiju from the Toho films to attract audiences; it would almost be a shame to just casually throw in Kumonga and Anguirus as well. With Rokmutul, however, the movie could reveal a cool and sadly unused monster from the first movie rather than letting that design go to waste. By using each new movie to reveal never-before-seen kaiju, the MonsterVerse can keep hardcore fans on their toes and keep the franchise feeling fresh.

Of course, there's a strong possibility that there weren't just be two more kaiu in Godzilla: King of the Monsters. The trailers have teased the Titans emerging en masse to reclaim the planet, so the shots of the kaiju emerging from beneath the oil field and mountain may be part of a bigger montage - perhaps even from the end of the movie, to set up the events of Godzilla vs. Kong. We're certainly looking forward to seeing these creatures in their full glory.

More: Godzilla 2 Trailer, Cast, Every Update You Need To Know

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