Ghidorah's name is made canon in the MonsterVerse thanks to Godzilla: King of the Monsters' viral website. Leading up to the movie's first trailer release during San Diego Comic-Con in 2018, Warner Bros. and Legendary Entertainment launched their viral marketing campaign to start promoting all the new monsters in the shared universe. That meant getting the ball rolling on introducing general audiences (and Toho fans) to the MonsterVerse's versions of Mothra, Rodan, and Ghidorah.
Thanks to the Monarch Sciences website, which is meant to house Monarch's research on all the Titans in the MonsterVerse, it's explained that Ghidorah (or Monster Zero, as the iconic creature was named by the shadowy organization) was discovered in 2016 by Vera Farmiga's Dr. Emma Russell, and that it has been on the planet for centuries. Given that Ghidorah is one of Godzilla's fiercest enemies, it's a bold move by the studio and the filmmakers to put the monster up against the defending Titan in Godzilla's first sequel, rather than save it for a potential Godzilla 3.
Related: Godzilla: King Of The Monsters Reveals A New Ghidorah Power?
When it was first announced that WB would be putting Ghidorah into Godzilla: King of the Monsters, fans wondered just how much of the monster's Toho origin and characterization would transfer over to the Western adaptation. Well, according to the latest Godzilla: King of the Monsters trailer, it looks like Ghidorah's alien origin is being made canon, and now thanks to the Monarch site, so is the Titan's name. Sure, Monarch classifies Ghidorah as Monster Zero, but it's noted at the end of its file that the "ancients called it Ghidorah."
What's more, Monarch even confirms that Ghidorah doesn't have a specific gender, unlike Mothra. This has been a sticking point for many Toho fans, and it's great to see it also being translated into Godzilla: King of the Monsters. So, just as Godzilla's original Gojira name was revealed by Ken Watanabe's Dr. Serizawa in Gareth Edwards' 2014 Godzilla movie, Ghidorah's name may, at one point, be uttered by one of Monarch's scientists in the new film. Sure, they may refer to Ghidorah as Monster Zero at first, since it certainly appears to be one of the oldest Titans on Earth, but they could then start referring to it by Ghidorah's Toho name.
Of course, there's still quite a bit that remains unknown about Ghidorah, as well as the Titan's role in the overarching shared universe. What we do know is that Ghidorah is currently stuck in Antarctica, where it's being monitored by Monarch scientists, who've determined that each of Ghidorah's three heads possess unique cognitive functionality; essentially, each head represents a different personality. And since three actors portrayed Ghidorah during production, seeing how all three of them react in a fight with Godzilla is certainly going to be interesting.
