Godzilla: King of the Monsters secretly added an unexpected plot device to the MonsterVerse. The movie reveals that telepathic mind control, a major science fiction movie trope, is possible in the world of Godzilla, and was in fact practised by ancient civilizations in order to control the Titans. Moreover, this form of control could make a comeback in the present day, in the form of Orca technology.
The redacted text in the credits of Godzilla: King of the Monsters provides some surprising revelations about the history of the MonsterVerse, particularly in terms of the relationship between mankind and Titans in ancient times. Included in the text is a long and detailed story about humans going to war with Titans. Though the humans of the underwater city did indeed worship the giant monsters, that eventually changed after humans found ways to telepathically communicate with Titans. Whatever these methods were, they developed into something much more sinister than telepathic communication: man found a way to control Titans and weaponize them for their own purposes. It was only when the Titans rebelled against their human masters that the war between the species kicked off.
Before the war, ancient civilizations were able to make Titans do their bidding. What humans did to the Titans thousands of years ago sounds suspiciously like mind control. This means that humanity is actually capable of mind-controlling the kaiju in the MonsterVerse. If so, modern humans could repeat the mistakes of their ancestors by using Titans as weapons, whether it be against other Titans or against rival civilizations. The last time this happened, it resulted in an Ice Age.
That being said, mind-controlled monsters in a Godzilla movie wouldn't be a novelty. Humans (and aliens) have been controlling kaiju to suit their own purposes in Toho movies since the 1960s. Godzilla, Rodan, Mothra, Anguirus, and even King Ghidorah have all been victims of mind control. Sometimes monsters were mind-controlled by aliens to attack humans, and on other occasions humans used similar methods to make the kaiju defend them. One of the most well-known instances came in Destroy All Monsters, when humans used their technology to send Godzilla and his fellow monsters to drive off King Ghidorah.
If, how, and when mind control would be implemented in the MonsterVerse remains to be seen, but the Orca is a possible first step. It was introduced in Godzilla: King of the Monsters to communicate with Titans by using frequencies detectable to Titans. If this technology received some advancements, it could potentially evolve into a device capable of directly controlling Titans. The consequences for this could be just as catastrophic for modern civilization as they were for the ancient humans - and could also explain why two seemingly benevolent Titans end up going to war in Godzilla vs. Kong.
