During the 10 year build-up to Avengers: Infinity War, we got to see Earth’s Mightiest Heroes grow into the powerful beings they became, but on the outside – among the stars – an evil being known as Thanos was biding his time before he unleashed a full-scale assault on the galaxy in search of the Infinity Stones.

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Many superheroes fell standing up to the Mad Titan, and it proved that greater threats exist in the cosmos, but they finally defeated Thanos. There’re plenty of aliens much stronger and just as capable as causing a huge problem for the Avengers, so we look as 10 cosmic threats we could see in Phase 4 of the MCU.

10 10. Annihilus

Annihilus demonstrates his rage

The Annihilation Wave was responsible for destroying millions of lives, the destruction of Xandar. And the imprisonment and torture of Galactus. It pushed Nova and the United Front to its limits, and almost saw the end of an entire galaxy, but in the end, the evil insectoid Annihilus was defeated.

Seeing such destruction would alert the Avengers – whomever the line-up – and introduce new heroes like Nova and Phalanx to the MCU. This could be a way off, as it features Drax’s daughter Moondragon, as well as Captain Marvel’s, but we know that the comic adaptions haven’t always been strict at following the source material. Annihilus is intent on obliterating everyone so that he can exist alone, much worse than the ideals of Thanos, so it's certainly a potential storyline for Phase 4.

9 9. Kang The Conqueror

Nathaniel Richards has proved a thorn in the Avengers’ side time and time again, so it makes sense to see him pop up in the MCU. Kang the Conqueror made a huge impact when he arrived on Earth in Washington DC, taking out the US Army with ease.

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The Avengers were soon contacted to help take care of the time-traveling human, but he dispatched them easily. Having Kang arrive unannounced on the White House lawn, blowing up the President’s home then threatening humanity would be a big enough alarm to alert the Avengers, and post-credit scenes from the films leading up to this moment could show some of his early escapades in ancient Egypt.

8 8. Galactus

Before the MCU, Galactus appeared in Fantastic Four: Rise of the Silver Surfer, and to say it was underwhelming would be an understatement. The Devourer of Worlds is an almighty presence, and finally seeing him in all his glory in the MCU would be incredible.

Whilst Kevin Feige and company may be saving him for when the Fantastic Four are introduced, he could still be teased through references and post-credits scenes, and Phase 4 could even have the Silver Surfer or other Heralds of Galactus fight the likes of Thor or the Guardians of the Galaxy before they arrive on Earth.

7 7. Korvac

Michael Korvac Avengers

Whilst not all threats are as huge as Galactus or as deadly as Annihilus, some can still be a threat to the Avengers. Korvac aided the Badoon when the alien conquerors decided to invade Earth, and in response turned him into a cyborg, however, his newfound powers went to his head and he turned on the Badoon in the process.

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He also took the Power Cosmic from Galactus’ starship, and harnessed some of the Grandmaster’s power, so he’d be a perfect enemy to the Guardians of the Galaxy – eventually spilling over onto Earth and bringing the Avengers into the mix.

6 6. The Beyonder

The Beyonders were an alien race known for creating the Cosmic Cubes, however, one of the Cubes became sentient, resulting in the evil entity known as The Beyonder. In Secret Wars, he created Battleworld for the sole purpose of seeing various superheroes to fight each other so he could satiate his curiosity.

Imprisoning superheroes on Battleworld could create an interesting take on the MCU, and help to introduce Molecule Man, and later on Kosmos – a unity of Molecule Man and The Beyonder. Phase 4 is ready for a new cosmic threat and introducing the Secret Wars story would offer a different approach that the typical alien wants to conquer Earth again.

5 5. Abraxas

Abraxas is the yin to Eternity’s Yang – the embodiment of destruction whereas Eternity’s purpose was that of creation. He might be a left-field choice to be the Fantastic Four’s enemy in the MCU, so he could appear as a threat to the Avengers in Phase 4 of the MCU instead.

The Ultimate Nullifier was used by Mister Fantastic to destroy Galactus, so maybe we won’t see Abraxas in Phase 4, however, seeds could be sown in the new Guardians of the Galaxy film to see him appear with Eternity, as there’s no bigger threat than the incarnation of devastation, and we all love a bit of that.

4 4. The Shi’ar Empire

Hailing from Chandilar, the Shi’ar are a race of aliens that find new worlds and absorb them into their own, known as the Shi’ar Empire. They are highly advanced, and their military is incredibly powerful, overseen by the Majestor or Majestix.

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Whilst Lilandra Neramani seems to have been in the recently released X-Men: Dark Phoenix, the Shi’ar Empire is yet to feature in the MCU, so their thirst for conquering worlds could spill into Earth-616 and pose a great threat for the superheroes of MCU’s Phase 4. Depending on when the X-Men are introduced, this could be the first big story for the mutants.

3 3. Adam Warlock

With the hint that Adam Warlock is already going to play a part in Guardians of the Galaxy 3 thanks to his gestating in the golden cocoon created by Ayesha – leader of the Sovereign, it seems we'll soon see him appear. Warlock is the epitome of perfection, created to embody almighty strength and intelligence, and although his introduction into the MCU is much different to his first appearance in the comics, it looks like he could pose quite the threat for the Guardians.

We might even see The Magus appear in the MCU – a version of a corrupted Warlock from 5,000 years in the future – but it seems more likely that once he appears from the cocoon, he’ll head right for the Guardians, and then towards Earth.

2 2. Aegis And Tenebrous

Aegis, Lady of all Sorrows, and Tenebrous of the Darkness between, are Promenial Gods – the first creations of our Universe – and are immensely powerful. Deemed a global and universal threat by the Nova Corps, Aegis and Tenebrous are capable of untold amounts of destruction.

Whilst they haven’t featured heavily in the comics outside the Annihilation event, that doesn’t mean they won’t appear in the MCU’s Phase 4. They could engage in a war with the Guardians of the Galaxy, fight against the new iteration of the Avengers on Earth, or even feature in the rumoured Nova movie. Whatever happens, they’ll be worthy opponents to the superheroes of the next phase.

1 1. The Celestials

Perhaps the most devastating threat in the entire universe, the Celestials are a race of immortal space gods that have played a huge role in many of the comic’s biggest events. They created the Eternals and the Deviants, as well as inflicting the X-Gene on Earth, and are deeply entwined with the entire history of the Marvel Comics Universe.

They’ve already threatened the Avengers on Earth, when the Dark Celestials unleash a destructive Horde, and have played a role in the lives of the Asgardians as well as the Guardians of the Galaxy, so there’s plenty of material for Disney to adapt.

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