The Marvel Cinematic Universe has only used two of the greatest threats from the comics. When Marvel Studios launched the MCU back in 2008, nobody could have possibly imagined how influential it would be. Marvel has become the hottest franchise in Hollywood, with rival studios still trying (and oftentimes failing) to mimic the success of the shared universe model, and Avengers: Endgame is the second highest-grossing movie of all time.

The first decade of the MCU is known as "The Infinity Saga," because it is dominated by the story of Thanos and the Infinity Stones. The stakes gradually increased over the course of the following years until finally in Avengers: Infinity War Thanos snapped his fingers and erased half the life in the universe. A year later, Thanos and the Avengers had an unforgettable rematch, with Captain America finally uttering the immortal words "Avengers assemble" Many viewers feel this moment simply can't be exceeded, in part because it's difficult to imagine any threats more chilling than Thanos, whose insane mission to rebalance the universe resulted in so much death and destruction.

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However, Marvel Comics' Captain America Annual #1 reveals just how unfounded those doubts really are in a key scene in which Steve Rogers reviews the Abaddon Index - a SHIELD file identifying the most dangerous threats in the Marvel universe. They include Thanos and the Infinity Stones; Galactus, the Devourer of Worlds; the interdimensional being Shuma-Gorath; Marvel's version of the devil Mephisto; the mutant supremacist Apocalypse; and an unseen sixth entry. The most striking thing about that list is that only two of the listed threats - Thanos and the Infinity Stones - have appeared in the MCU to date.

The comic perfectly illustrates just how many concepts and ideas Marvel Studios has to play with. Every one of these six villains could be as big as Thanos if handled well, their story dominating multiple phases of the MCU just as Thanos' did. And now is the perfect time, considering Marvel Studios only regained the movie rights to some of these characters after Disney purchased the bulk of Fox's film and TV empire. Apocalypse is associated with the X-Men franchise, while Galactus and probably Annihilus are tied to the Fantastic Four, meaning they were Fox properties. And these are only the Thanos-scale enemies, the villains who - according to Captain America Annual #1 - should be considered extinction-level threats.

This one panel underlines just how bright the future of the MCU really is. Marvel Studios has barely begun to dip into the potential of the comics, and new books are published every week, meaning there are ever more stories and characters for the MCU to draw upon. Thanos may have dominated the first three phases of the MCU, but the franchise doesn't need him for its future to be secure.

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