One of the year's most anticipated movies has finally been released on HBO Max and in theaters. Godzilla Vs. Kong features the two title characters duking it out in this year's first blockbuster release. Serving as the fourth entry in Legendary's monster verse, fans can finally find out who the apex predator is.

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While the fight between Godzilla and Kong may be the main attraction in this movie, the franchise fans will recognize and appreciate plenty of references when watching. Some are more obvious nods to past films, while others are easy to miss. Here are some easter eggs only the most dedicated monster verse fans will spot.

11 The Truth Of The Hollow Earth Theory

A desk bearing Nathan Lind's book "Hollow Earth"

At the beginning of the movie, Dr. Nathan Lind shares his theories on Hollow Earth. This hypothesis states that a habitable portion of the planet beneath the surface was home to massive creatures in the past.

Those who have seen the previous entries in this franchise will know that the universally panned theory holds weight in this world. It's given credence in both Godzilla: King of the Monsters and Kong: Skull Island. It's where most of the monsters live and part of the reason they can go unnoticed for years. Those who have seen the horrors beneath the earth's surface rarely live to tell the tale.

10 Allusions To Kong's Ancestors

Godzilla vs Kong handprint

When an expedition team accompanies Kong on a trip to Hollow Earth, the giant ape finds eerie giant handprints plastered on the walls throughout the area.

These prints further confirm that the Hollow Earth theory is true: the Titans did call this habitat their home. Kong may be the last of his kind, but those before him left several keepsakes that he could claim as his own.

9 The Significance Of Kong's Axe

Kong holding the axe

The handprints aren't the only thing Kong discovers on his trip through Hollow Earth. He also finds an ancient weapon, an ax of gargantuan proportions. It's a weapon only a Titan could fashion and showcases the intelligence that the titanic apes possessed.

This weapon serves as an integral part of Kong's journey, but there's more to it than just that. The axe also holds ties to the king of monsters himself, Godzilla.

8 Kong's Axe Is Made From Godzilla's Armor

Godzilla and Kong fighting in Hong Kong

When Godzilla and Kong face off in Hong Kong, Kong finds out that his weapon is useful in more ways than one. Not only is it an excellent tool in combat, but it can also absorb Godzilla's atomic breath. This is because the ax is fashioned from one of the kaiju's scales.

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Only a Titan could remove a scale from the king of monsters (or his ancestor) and use it as a weapon. It alludes to the war between Godzilla and Kong's ancestors, centuries before the confrontation seen in the film.

7 The King Of The Monsters Continues His Reign

Godzilla in the foreground, with Kong standing in the background

Those who have followed the most recent iteration of the monster verse know that all the monsters bow before Godzilla. In his most recent solo outing, Godzilla was crowned King of the Monsters when he defeated King Ghidorah.

At the end of Godzilla Vs. Kong, the giant lizard adds another victory to his record. After his decisive victory, he leaves Kong standing, much like the monsters that bowed before him in the last film. It seems even Kong knows when he's beaten and who the true ruler of the verse is.

6 Kong Has A Deeper Purpose

Close-up of Kong's face

Godzilla's focus may be on maintaining dominance, but Kong's mission is to find a place to call home. After being dragged away from Skull Island, he spends the entirety of the movie searching for freedom.

The titan is often caged and chained, forced to do the human's bidding. He never wants to fight, but is put in a position with no alternative. When the movie concludes, Kong calls Hollow Earth his home. He realizes that he is where he is from and where he belongs. It's a heartwarming moment that gives the ape a happy ending.

5 The Skullcrawlers Still Live

Madison, Josh, and Bernie find Skullcrawler eggs

When Madison, Josh, and Bernie explore the Apex facility's inside, they find massive sacks being monitored in a lab. These sacks are actually Skullcrawler eggs. For those who haven't seen Kong's solo film, this reference won't mean much.

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However, those familiar with Kong: Skull Island know that these fearsome creatures crawled up from Hollow Earth, and without Kong, the island's residents would have been defenseless. Each one was strong enough to take out a platoon of trained soldiers. Apex uses them for research and experimentation, as they plan to create an Apex predator of their own.

4 The Return Of Mechagodzilla

Mechagodzilla in Godzilla vs Kong

Those familiar with Godzilla and his monsters' catalog will undoubtedly recognize the metallic menace known as Mechagodzilla. This monster first appeared in 1974's Godzilla vs. Mechagodzilla, where he served as an extraterrestrial antagonist.

In Godzilla Vs. Kong, this cybernetic creature is an Apex creation. He serves as the final hurdle for Godzilla and Kong to overcome, and they'll have to work together to bring him down. It's an excellent recreation of the famous villain, one that franchise fans will love.

3 Nuclear Energy Powers The Titans

Radiation in Hollow Earth

At one point in the movie, Kong is on death's door, and the only way he can be saved is by injecting large amounts of energy into his body. The humans detonate a ship filled with enough power to power a city for a week directly on top of Kong.

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One concept shown in previous monster verse entries is that the Titans thrive on nuclear energy. It powers them up and strengthens them immensely. This moment reminds the audience that nuclear power is quintessential to Titans.

2 Godzilla's Former Foe, Ghidora, Powers Mechagodzilla

Ghidorah's skull in Godzilla vs. Kong

Mechagodzilla may have gained autonomy by the end of the film, but humans originally piloted it. The man controlling Mechagodzilla used King Ghidorah's skull as a hub to issue commands to the massive mech.

Those who saw Godzilla: King of the Monsters may remember King Ghidorah as the three-headed Titan that Godzilla took down with the help of Mothra. Apex uses the remains to fashion their own predator in this iteration, though they aren't able to control the beast as well as they'd have liked to.

1 Godzilla and Kong Have Fought Before — And May Again

Godzilla using Atomic Breath

While Godzilla Vs. Kong is the latest monster brawl to hit the big screen, it isn't the first. The Titans have faced off once before in 1962's King Kong Vs. Godzilla, in which the monsters fought each other with a different result. At the end of this movie, Kong was the victor.

With Godzilla being the loser last time, it makes sense that the director would switch things up in the most recent film. Now the score stands at one to one, and the pair may need a tiebreaker in the future.

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