When it comes to major blockbusters, it is difficult to keep any big secrets. The promotions for Godzilla Vs Kong so far have made the movie look like a matchup between a heroic Kong and a villainous Godzilla. But the final trailer for the film that was released on China's biggest social networking site Weibo has now officially given us the first clear look at the true villain of the film, the giant, man-made kaiju Mechagodzilla.

The creature is shown in the final few seconds of the trailer emerging from its containment area. The metallic scales on the back of the giant machine are shown first, followed by a closeup of its glowing red eye. The size of Mechagodzilla is difficult to ascertain, but if previous movies are any indication, it will be the same size as Godzilla.

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Apart from featuring Mechagodzilla, the trailer also hints at the arrival of another closely-guarded secret of the movie, the entry of the alien characters known as Xiliens. In previous Godzilla movies, the Xiliens were interplanetary invaders who used giant monsters to lay waste to Earth in preparation for conquering it.

In the trailer, Kong can be seen interacting with some blue-lit UFOs as the giant ape explores an alien world filled with levitating rocks, one of which might be used to create his new battle-ax. It is possible that the Xiliens will help Kong fight Godzilla in this film, before using the giant lizard and giant ape for their own nefarious ends in the next film.

Of course, Mechagodzilla and the Xiliens are the side dish. The main course that audiences are looking forward to in Godzilla vs. Kong is an epic match between the two leading icons of monster films. In a previous interview, producer Alex Garcia had stressed that neither character is the villain, but they are simply two creatures that are following their instinct for survival.

"It depends on how you're looking at [Kong and Godzilla]. I think they're both characters who are fighting for something, which is distinct to them. And those things happen to sometimes be what's good for us, but they don't always align. Neither of them is inherently evil, but they're also not inherently good, right? And I think that's where the complexity of us, of mankind, and our relation to them really come into play."

Now that Mechagodzilla has officially entered the Monsterverse, we know that at some point Kong and Godzilla will put their differences aside to deal with the mechanical monstrosity. It will be interesting to see how Godzilla will feel about having to team up with Kong, who belongs to a species of superpredator that are said to have been in a centuries-old rivalry with Godzilla's kind.

Directed by Adam Wingard and written by Eric Pearson and Max Borenstein, Godzilla vs. Kong stars Alexander Skarsgard, Millie Bobby Brown, Rebecca Hall, and Brian Tyree Henry. The film arrives in theaters and on HBO Max on March 31.