The first ever Marvel Studios novel, Thanos: Titan Consumed by Barry Lyga, may have dropped a tantalizing clue that either the Celestials or the Horde will be the new villains in Avengers 4. Although little is known about next year's Avengers sequel, there's some evidence that Thanos won't be the only enemy the Avengers need to take on. Leaked toy box descriptions have teased "new foes" and "an even greater threat."

This important clue appears in Barry Lyga's novel, Thanos: Titan Consumed, which reveals Thanos' history. Although Marvel has clarified that the book isn't to be considered strictly canon, Lyga worked closely with Marvel Studios while writing it. In fact, while it was completed well before the theatrical release of Avengers: Infinity War, the plot shows an intimate knowledge of the film's narrative. Thanos: Titan Consumed accurately reproduces Gamora's recruitment, and teases a cosmic "out of body" experience for Thanos after he's snapped his fingers and accomplished his insane goal. If Lyga knew the events of Infinity War, it's entirely possible he also had some knowledge of Avengers 4, and that an element of foreshadowing may be visible in this story.

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In one scene towards the end of the book, Thanos is talking to a powerful being known as the Lorespeaker. The Lorespeaker has an intimate knowledge of the stories and legends of the cosmos, and he tells Thanos all about the Infinity Stones. Crucially, when Thanos asks why nobody uses these, he gives a simple explanation:

"They are hidden, Thanos," the Lorespeaker said, as though badgering a child, "because they are too powerful. And because the Celestials and the others, the ones whom the Celestials fear, keep close watch on the Stones from afar."

Everything else the Lorespeaker says about the Infinity Stones is correct according to the MCU's mythology. If he's right about this as well, then powerful forces still exist in the cosmos - beings of immeasurable power who keep a careful watch upon the Infinity Stones. The Celestials themselves are perhaps not quite so extinct as has previously been believed; it's possible Ego wasn't the last of his kind after all, but rather that the Celestials had retreated from the universe but continue to monitor it. Meanwhile, the reference to other forces - "the ones whom the Celestials fear" - is absolutely fascinating. Over in the comics, there isn't really any cosmic force the Celestials can truly be said to fear; the closest match is probably the Horde, an insect-like race who are agents of destruction. They can even target and infect Celestials, consuming the life-energy within them.

If the Lorespeaker's words do indeed foreshadow Avengers 4, then Earth's Mightiest Heroes could well find themselves confronted with either the Celestials or the Horde. If so, they really are about to take on a greater threat than even Thanos - they're dealing with cosmic races of life and death, forces who can judge entire worlds and civilizations. It can't be long till the release of a trailer for Avengers 4, which will hopefully offer some more clues.

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