Warning: Spoilers for Thunderbolts*!Avid fans of the Marvel Cinematic Universe are finally getting a taste of the Sentry. This character, who has existed in Marvel lore for 25 years, has officially been acclimated into the MCU. With his live-action debut in Thunderbolts* (now officially re-named The New Avengers), Sentry instantly becomes a major MCU player, even if his creator says Marvel misread him.

With that in mind, it goes to show that only so much about a comic book character can be adapted for the big screen without either leaving details out or misinterpreting the source material. In either case, this makes it all the more essential to explore the comics that inspired the MCU's Sentry. While the movie gave viewers a solid impression of Sentry and his villainous Void persona, both are portrayed as even darker in the comics. He's often oversimplified as an evil Superman, but his incredible feats make him far more dangerous.

8 Sentry's REAL Origin Story Is Darker Than You Thought

Dark Avengers #13 by Brian Michael Bendis, Mike Deodato, Rain Beredo, and VC's Cory Petit

When Sentry was first introduced into the Marvel Universe, his comic-styled origin story was simplified: a young Robert "Bob" Reynolds stumbled upon a serum in a laboratory belonging to a man aptly named The Professor. There wasn't much detail at that point because, at least back then, it didn't matter. Over the years, Marvel gradually revealed the full story of how Bob became the Sentry. After Bob's wife, Lindy, kills her murderous husband, she decides it’s time for the world to know exactly what happened to Robert Reynolds.

Lindy recalls that the reason Bob was in that lab in the first place, searching for the serum, was because he was looking for drugs to feed his addiction. Bob found the experimental drug by accident. His meth habit was what led him to stumble upon the world’s ultimate experiment. In his origin story in Thunderbolts, Bob is still a drug addict, but he volunteers for Project Sentry in hopes of becoming a better person. In the comics, he is actively searching for a high when he finds the serum, unaware of how it would change his life forever.

Bob’s origin story is first revealed in a brief flashback, presented in a classic comic book art style, in 2000's Sentry #1 by Paul Jenkins, Jae Lee, Jose Villarrubia, Richard Starkings, and Comicraft’s Wes Abbott.

7 It's True: Dark Sentry Once Broke Every Bone in Hulk's Body

Sentry #3 by Paul Jenkins, John Romita Jr., Mark Morales, Dean White, and Rus Wooton

More than just a supervillain alter ego, The Void acts as a dark enger within Sentry, antagonizing him at every opportunity, even when they’re separated. During a team-up in the Negative Zone with his friend, the Hulk, they find The Void waiting for them. The Void seems intent on teaching them both a lesson. For Sentry, it's The Void trying to convince Robert Reynolds to stop denying him. For the Hulk, The Void wants to capitalize on a promise made during their last encounter: to break every bone in Hulk’s body to make a point.

And so, he does, in record time, no less. That’s partly what makes The Void so scary and overtly dangerous here: the fact that it takes one of Marvel’s strongest heroes, the Hulk, and snaps him like a twig in seconds. Even scarier, The Void doesn’t do it out of malice or to settle a past vendetta, but to prove that it can. That is absolutely diabolical. As powerful as The Void proves to be in Thunderbolts, his actions here make his earlier scenes pale in comparison to what he does to Hulk.

6 Yep... Hulk and Sentry Totaled an Entire City

World War Hulk #5 by Greg Pak, John Romita Jr., Klaus Janson, Christina Strain, and VC's Chris Eliopoulos

Hulk's bone-crushing defeat came more so at the hands of The Void than the Sentry, but the two all-powerful dynamos wouldn't have a true face-to-face until the "World War Hulk" event. A sequel to the "Planet Hulk" arc, Hulk wages an all-out war against the planet Earth and its mightiest heroes, and the hero community's last line of defense is the agoraphobic Sentry. Fully aware of the damage his strength can do, Robert fears unleashing it, but Tony Stark urges him that he must if he wants to save the planet.

The pair of juggernauts tussle, resulting in a stalemate that calms the green giant. Unfortunately, Sentry's worst fears come true when their battle reduces the entire city around them to rubble. Iron Man and Sentry expected casualties, as Sentry needed to unleash the power of a million suns without holding back to reach a conclusion. However, this fight shows how his all-encoming power has consequences. It also shows the results of how dangerous Sentry's power can be if gone unchecked. This is the one time Bob decides not to hold back.

5 Sentry Killed His Own Sidekick

Sentry #5 by Jeff Lemire, Joshua Cassara, Rain Beredo, and VC's Travis Lanham

Some of the darkest things that Sentry has committed were under the influence of The Void, but in this particular sidekick-killing instance, it was all Bob Reynolds. Granted, this is a rare case where Sentry was justified in going dark. Rather than being the corrupted one, it’s his sidekick, Scout. Feeling jealous and bitter that his mentor had the power he always wanted, Scout conspires with Sentry’s archrival, Cranio, to recreate the Sentry formula at Bob’s expense. As Billy wreaks havoc throughout Manhattan, Robert is forced to embrace The Void to put a stop to his sidekick-turned-enemy once and for all.

With Sentry’s powers, Scout proved to be one of his most powerful opponents, but he also showed how he was quickly becoming a danger to the world around him. Bob had every reason to destroy his former ward, but that’s what makes this so dark. The teacher never wants to end the life of the student, much less stunt their progress after spending so much time sharpening their skills. Sadly, Bob had no choice. Not only had his protégé gone rogue, but he was struggling to hold onto the power that was killing him. Bob simply put him out of his misery.

4 The Time Sentry Gave Molecule Man a Taste of His Own Medicine

Dark Avengers #12 by Brian Michael Bendis, Greg Horn, Mike Deodato, Rain Beredo, and VC's Cory Petit

In Dark Avengers #11, Bob meets Owen Reece, a.k.a. The Molecule Man. Owen seemingly ends Sentry's life by splitting his molecules (and body) in half, but in the next issue, Sentry pulls himself back together. It is at this moment that Sentry discovers his god-like superpower of molecular manipulation. He's quick to put this power to use by basically torturing the Molecule Man with his own powers. He orders Owen to undo the damage he has done to the world over the past couple of issues, and then evaporates The Molecule Man in an instant.

Sentry has always been a powerhouse, but that power is best exemplified by seeing how he reacts to his abilities evolving in real time. He doesn’t flinch, nor does he struggle to use his new powers better than the master of molecule manipulation himself. He doesn’t hesitate to use these new powers with the intent to kill. His killer instinct is unmatched in ways that set him apart from other heroes, making him a formidable adversary. It’s even scarier when he’s willing to get what he wants by torturing, not just killing.

3 Sentry Literally Ripped Ares Apart

Siege #2 by Brian Michael Bendis, Olivier Coipel, Mark Morales, Laura Martin, and Chris Eliopoulos

Similar to how Sentry s the New Avengers for Valentina Allegra de Fontaine onscreen, he s the Dark Avengers for Norman Osborn on-. On orders from the Director of H.A.M.M.E.R., Sentry and co. embark on phase one of a siege on Asgard in an effort to shift the country's status quo into his image. Ares defends The Mighty Thor from being arrested, instigating a one-on-one fight between himself and Sentry. It's worth noting that beyond being gaslit by the former Green Goblin, Sentry turns into the Void during this ensuing brawl. Ruthless and relentless, Sentry rips Ares' body in half.

This has to be Sentry's most infamous and darkest moment, and with good reason. It's the moment that manages to be most frequently shared online and frequently ed by anyone remotely familiar with Sentry. Spread across two pages, it's a moment that single-handedly showcases the level of strength that Sentry possesses as well as the full level of brutality that he encomes once consumed by The Void. And that still isn't his coldest moment in the comics, as Sentry's epic quote shortly after gives everyone enough cause to fear him forever: "How many Gods will I have to kill today?"

2 Sentry Became an Undead Zombie and Tore His Own Flesh Apart

Uncanny Avengers #11 by Rick Remender, Daniel Acuna, and VC's Clayton Cowles

In the comics, Sentry's darkest path leads him to be reanimated as one of the Four Horsemen of the Apocalypse, serving the Apocalypse Twins, Uriel and Eimin. The Death Seed grants him a powerful upgrade, and he first targets the man who killed him in battle, Thor. In their rematch, Sentry claims that The Void is out of his system, apparently residing in the White Hot Room's lighter side. But this is a twisted, undead version of Sentry, one so demented that he is willing to tear his own face apart while dismantling his enemies.

In their first encounter, Sentry leaves Thor knocked out. In the second, he nearly kills The Wasp, only for Thor to intervene just in time. Even then, the Mighty Thor narrowly escapes death thanks to a well-timed planetary worm. Becoming a soldier of Apocalypse pushes Sentry to the most unhinged state he has ever been in, whether or not he is burdened by The Void. While The Void would force Bob Reynolds to commit unforgivable acts of villainy, this arc proves that even without it, Sentry can still be disturbingly methodical in his madness.

Sentry's deadly encounter with Wasp happens in Uncanny Avengers #15.

1 Sentry Lends His Powers to an All-New, All-Evil Sentry

Sentry #1 by Jason Loo, Luigi Zagaria, and VC’s Joe Caramagna

Thanks to Knull, the King in Black, Bob Reynolds has been long dead, but the powers of the Sentry live on. Today, they belong solely to Mallory Gibbs, who rechristens herself as Marvel's newest hero, Solarus. Before that, however, the powers of the Sentry transition to her and five other ordinary people. Among them is Ryan Topper, who, unlike his peers, is eager to use the powers of the Sentry for more selfish reasons. He claims he wants to use them to become a powerful superhero for the greater good, but in reality, Ryan simply craves the power.

This desire leads Ryan to go out of his way to kill everyone else who has been gifted the Sentry's powers, hoping to absorb them all and keep them for himself. Even after Robert is long gone, his powers can still be misused and abused if they fall into the wrong hands. The monster that is Ryan Topper would never have been unleashed upon the world if Bob hadn't discovered the Sentry formula long ago. Robert's transformation into the Sentry turned him into a monster, and in turn, it birthed another.