Although Godzilla vs. Kong, he alone won't be enough, and the MonsterVerse movie should feature multiple opponents for Godzilla and Kong to fight. Of course, the focus of the movie will be their battle against each other, but there's an expectation that at some point in the film, Godzilla and Kong will put aside their differences and team up against a common threat.
Due to a recent delay, Legendary's Godzilla vs. Kong is still several months away, so it's hard to say when the trailer or any other official details on the movie will be released. Even at this stage, not much is known about the plot, but leaked images at a convention in Hong Kong did certain teases in the credits of Godzilla: King of the Monsters offer hints about how Mechagodzilla will be implemented in the story.
The question is, will Mechagodzilla be the only villain in the movie, or will he be ed by other Titans, manmade or otherwise? Like King Ghidorah, Mechagodzilla is easily one of the toughest opponents Godzilla has ever faced, but he shouldn't be the only foe faced by Godzilla and Kong in the movie. First of all, it wouldn't make for an exciting battle, particularly since audiences will expect Godzilla to be strong enough to defeat Mechagodzilla on his own. In facing Godzilla and Kong, Mechagodzilla will have the odds stacked against him, and in a way, these circumstances would lower the stakes of the fight.
Godzilla has already been established as the King of the Monsters, so his claim to the title would be significantly weakened if he required Kong's help to beat any single villain. One could argue that Godzilla needed help to beat Ghidorah, but this is a different situation, since King of the Monsters made it clear that Godzilla is indeed capable of defeating Ghidorah one-on-one. For their last fight, Ghidorah was powered up by his energy absorption ability, even more so than Godzilla.
There shouldn't be any one Titan powerful enough to challenge both Godzilla and Kong, much less Mechagodzilla. Though it's true that Godzilla has gotten help from kaiju like King Caesar and Rodan in the past, "Godzilla vs. Mechagodzilla" means something special in the MonsterVerse, because it carries on the theme of humanity versus nature that's been prominent in all three MonsterVerse movies, and each time, nature always wins. As important as this concept is to the MonsterVerse, Godzilla vs. Kong should continue to embrace it, and have Godzilla beat this manmade Titan unaided.
The best solution to the villain problem is to give Mechagodzilla allies, such as Mecha-King Ghidorah, Biollante, one or more of the existing MonsterVerse Titans, or perhaps an all-new monster. If Godzilla really is the King of the Monsters and if Kong is powerful enough to be a contender for that title as well, multiple villains should be needed to provide a truly epic final showdown in Godzilla vs. Kong.
