'Captain America: Brave New World': How The Leader's Post-Credits Warning May Hint At An MCU Favourite's Importance Come 'Secret Wars'

WARNING! SPOILERS for Captain America: Brave New World.

The latest MCU blockbuster Captain America: Brave New World has hit theatres, starring Anthony Mackie as Sam Wilson, in his first big screen adventure since officially taking up the Shield and mantle of Cap. While reviews for the film as a whole have been mixed, Mackie's performance has been praised. The film also sets the stage for the future of Earth's mightiest heroes in the Marvel Cinematic Universe, with Sam ending the film having come to the conclusion that the world still needs the Avengers, and is ready to assemble a new team.

On top of this, the film's post-credits scene has excited comic-savvy MCU fans, who believe a warning that villain The Leader delivers to Sam could hint at an important role for a a fan favourite character as we head into the Multiverse Saga's conclusion, Avengers: Secret Wars, in just two years time.

Let's take a little look at The Leader's history, his warning, and the possible hint fans have picked up on.

Origins of The Leader

The Leader, then cellular biologist Doctor Samuel Sterns, was introduced back in 2008's The Incredible Hulk film. Using the alias of Mr. Blue, Sterns is an ally of Bruce Banner, working together on a cure for Banner's Hulk transformations. Banner occasionally sends Sterns samples of his blood for this purpose. However, when they meet in person later in the film, it is revealed that Sterns has synthesised a large supply of the blood, wanting to use it for medical research. Bruce, horrified, wants the blood destroyed.

Before this can occur, Bruce is taken into custody by Then-General Ross, and Russian soldier Emil Blonsky, coveting the power of the Hulk, forces Dr. Sterns to inject him with one of Bruce's blood samples. The blood reacts badly with the bootleg Super Soldier serum Blonsky took earlier in the film, transforming him into The Abomination. In Abomination's subsequent rampage, Sterns is injured and also infected with the blood.

Brave New World reveals that the gamma-radiated blood affected Sterns' brain, giving him the ability to predict outcomes based on probability percentages, eventually naming himself The Leader. Rather than try to cure Sterns, Ross imprisons and exposes him to more Gamma, advancing his abilities so that he may make use of them. He also has Sterns create medication for his failing heart.

The Leader's Warning

Unbeknownst to Ross, Sterns had laced his medication with Gamma radiation, eventually triggering his transformation into Red Hulk. Sam Wilson was not initially a target of Sterns beyond his role in the sequence of events leading to Ross's transformation, but earns The Leader's ire when his ability to adapt on the fly means the new Captain America often acts against the villain's projected probabilities.

Sterns is re-imprisoned, this time in The Raft, by the end of the film. In the post credits sequence, he is visited by Sam. Sterns warns Sam that he has seen what is coming in 'the probabilities', and that he may be unable to protect their world from other worlds.

This is most likely a reference to the multiversal conflict set to unfold in Avengers: Secret Wars. Judging by Sterns' rather smug demeanour in the scene, it seems he believes in a high probability that Sam and whatever team of Avengers he manages to assemble will lose the coming battle. However, fans with comic knowledge believe that a certain fan favourite character's return could provide hope for the heroes we know and love.

It's all in one word: probability.

A Chance at Redemption for the Scarlet Witch

Wanda Maximoff, aka the Scarlet Witch, last appeared back in Doctor Strange in the Multiverse of Madness. After a villain turn, she shakes the influence of the Darkhold, collapsing Mount Wundagore to destroy the Darkhold's original copy, and every copy throughout the universe. In-universe, she is assumed to have been killed in the collapse, but few fans believe this is true.

Recent rumours suggest that Wanda is set to play a major role in Avengers: Doomsday, and will be on a quest for redemption. She may initially work with Dr. Doom for this purpose, only to eventually discover that doom poses the greatest threat.

Wanda's recent MCU appearances have leaned heavily into the rare chaos magic she possesses as the Scarlet Witch. While Wanda also gains this magic in the comics, she only taps into it fully in dire situations, due to the adverse affect too much reality warping can have on her mental health.

The Scarlet Witch's original powerset, and one that she still commonly utilises in present day comics, is the power to alter probability, with what she calls probability hexes, or hex spheres. The more improbable an event seeems, the greater ability Wanda has to make it happen.

The Leader's prediction of a bad outcome for The Avengers in Secret Wars is based entirely on probability. However, it is possible that if Wanda appears in the film, she could alter those probabilities in favour of the heroes, even if victory seems unlikely, and possibly gain the redemption she hopes for.

We'll have to keep an eye out for more clues in the coming films and shows.