The Sentry is a character that is often forgotten about, both in the pages of Marvel Comics themselves and among their fans. Created in 2000, in The Sentry #1, in some ways the character is Marvel's attempt at their own Superman, although with an added twist.

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Sentry has actually been involved in some major story lines over the years and has been both a threat and a friend to the Avengers. What's forgotten most about the character (who also goes by the name of Robert Reynolds), though, is the fact that he's actually one of the most powerful heroes across the Marvel Universe. Let's take a look at why.

10 THE VOID

The Void unleashed emitting massive amounts of energy

The first crucial detail about the Sentry that anyone new to the character needs to know? His arch-enemy is called the Void. This entity is more of a creature than a man. It's extremely destructive and is capable of wrecking not just the planet, but perhaps the whole universe.

Unfortunately, this very violent force is actually a part of the Sentry. The Void lives within Reynolds and is a part of his very being. He constantly struggles with the force and it's part of what makes the man so dangerous. The Void can be unleashed at any time, and the worst part is that Reynolds doesn't really even know that he is his own worst enemy!

9 UNPREDICTABLE AND UNSTABLE

Because of this constant internal battle that Robert is fighting, the character is often unpredictable and unstable, which makes him incredibly dangerous. This is terrifying in itself, as you need somebody who wields this level of power to be responsible with it (remember what Uncle Ben said).

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Sentry can often be seen actually talking to himself, as the Void is playing tricks inside his head, often mocking him or trying to throw him off his game. When you're talking to Reynolds, you're not always sure who you are talking to either, but you have to hope that it's the Sentry getting the message and not the Void.

8 EASILY MANIPULATED

Another issue with Sentry is that, compared to other Marvel Heroes, he is actually really easily manipulated. There's a certain naivety that comes with the character and this could be especially deadly.

With such a power-set and so much destructive force, you don't want a character like this getting used in some way but the villains of these comics. This is exactly what happens, though, showing just how dangerous this hero is. As with the likes of the Hulk, he can be a real liability.

7 DARK AVENGERS

During the Dark Reign story line, Norman Osborn created his own team known as the Dark Avengers. It consisted of the villainous versions of some of Earth's most powerful heroes, but to give it some legitimacy, it also included SentryThroughout his time with the team, though, Reynolds was constantly manipulated.

He didn't realise he was actually working with villains, which meant that his powers were often being used to reinforce this terrible rule over America. Reynolds was used when his wife came into danger and was eventually murdered by his team member, Bullseye. This was to continue to maintain a level of control and focus over the hero.

6 EXTREMELY EXPERIENCED

Despite his naivety, in terms of battle and using his powers, Sentry is actually very experienced, which makes him an even bigger threat. Although the character was created in the 2000s, the hero has actually been around for a lot longer in the lore of the comics, although no-one remembers him!

The character was supposedly around during the golden age of heroes and had actually met some of the other famous Marvel characters in the past. Very few knew who he was upon meeting him again, but Reynolds actually has the experience of a long-time hero, which is very useful.

5 HIGH POWER LEVELS

We've already spoken about the absurd levels of power that the Void possesses, but what about Reynolds himself? How powerful is he, really? His abilities have been debated for some time, as no-one truly knows where they come from. Some think it's a type of Super Soldier Serum, but others believe him to be a being from another galaxy or universe.

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The limits of his powers are also unknown, if they are indeed limited. He does have the power of flight, super strength, invulnerability, increased speeds when flying, and energy manipulation, alongside so many other skills. On top of this, he usually holds back, because of how ridiculously strong he is.

4 ONE WEAKNESS

Just like any other hero, Sentry does have one weakness that can be used against him to control him. It's also a weakness that can hold him back when he is out of control, though. Reynolds is deeply in love with his wife. She can therefore be used as a weapon against him, but can also talk him down.

Unfortunately, Norman Osborn went too far, having his wife killed. With nothing to hold this hero back, there's really no other weakness to utilise, making him far more dangerous than every other Marvel hero. Usually family is the key, but without a family Sentry has nothing else to lose. That's a terrifying thought.

3 KILLED ARES

After being manipulated for so long and becoming tired of his battle with the Void, Sentry eventually succumbed to the dark in him. During the Siege event, the character unleashed all of his power. During the ensuing fight, Reynolds did something truly terrifying.

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He took the God of War, Ares, and ripped him in half. This made a statement and sent out a sincere warning to the supervillains (and superheroes) of the universe: You cannot fight Sentry when he is tapping in to all of his power. It's a very  shocking splash page, but it makes a strong point.

2 DEFEAT OF THE AVENGERS

You realise just how powerful the character is once you see him against the other heroes of Marvel, though. During the same story arc, Sentry continued to lay waste to some of Marvel's most iconic characters.

They were truly no match for the power of this god amongst men, as he nearly destroyed every last one of them. It's an intense moment, and if it wasn't for some use of magic, perhaps Earth's mightiest might have been killed in action. With these unrivalled abilities, it's no wonder he really is terrifying. Who can stand against him?

1 SURRENDER

The scary thing about this character is that he is unstoppable. There's just no way to beat him. The heroes never do. The only way that this conflict ends is by Sentry actually surrendering himself for a split second, before the Void returns again.

He is killed in this moment and placed in the heart of a sun, in order to truly end one of the most powerful heroes in history. The character, much like any other comic hero, is later revived and is presented as even more godly, showing just how superior he is to some of Marvel's other heroes. It's a terrifying power and one that isn't always in the right hands.

NEXT: Earth's Mightiest: The 15 Strongest Avengers Ever