The Hulk is a massive creature, with strength that makes him one of the strongest superheroes on Earth and in the Marvel Universe. Most of The Hulk’s early appearances were guest roles in other superhero comics (his first series was 6 issues long.) Eventually, he began appearing in his own series, taking on his own adversaries. But for the most part, The Hulk has had the same power throughout his decades of comic book appearances. Although some powers appear to manifest themselves randomly, they are always derivative of current abilities, just explained or shown in a different way.

When Bruce Banner changes to The Hulk, the body is such a drastic contrast that it’s hard to believe there are any weaknesses. There aren’t many, but enough to balance out the ridiculous amount of powers The Hulk has. More importantly, if you think The Hulk’s body is a straightforward mass of muscle and anger, then you may not have heard about the lesser-known abilities The Hulk has, many of which are simply weird when you think about it.

This list focuses on The Green Hulk’s body, and the strange facts surrounding it. He’s not all strength when in Hulk form, and not all intelligence when he reverts to his regular form, Bruce Banner. There are entries about the comic book Hulk and the Marvel Cinematic Universe Hulk to prove the weirdness isn’t contained to one media.

Here are 20 Weird Facts About The Hulk’s Body.

Doesn’t Need Oxygen

Humans who can hold their breathe for minutes at a time are impressive. The world record is 22 minutes underwater by a Denmark citizen, who destroyed his own previous record. However, The Hulk could easily surpass that.

Occasionally, The Hulk doesn’t even need oxygen to survive in extreme conditions. Whether this is a factor of his body adjusting to current conditions - fighting and situational - or just an innate ability remains to be seen. No matter the case, The Hulk can make any surroundings inhabitable to others hospitable to him. There have been a few comics that showed him surviving in the vacuum of space. There have also been instances where The Hulk talks, but it’s clear he can’t be breathing to inflect or enunciate words or sounds.

Even his signature grunt takes oxygen, but he finds a way to emit it without a breath.

In rare cases, The Hulk manages to fight and maneuver underwater with little effort, and for extended periods of time. So if The Hulk can operate without breathing in some cases, does his body somehow know to store up oxygen to use moments before?  We’ve seen The Hulk fight anywhere, anytime, so this is a handy ability to have.

Mark Ruffalo’s Weight Loss

When Mark Ruffalo took the role of Bruce Banner/the Hulk, most of the preparation came from Ruffalo’s physical appearance and how he wanted to portray the two characters. Ruffalo wanted to “do this much in the way I think Bruce Banner does it.” Meaning, Ruffalo wanted to live a clean life. Banner does it to stay on top of his rage; Ruffalo did it for the part, but also because he “had been feeling a little sluggish.” Ruffalo felt Banner was “rakish and thin” and “looks like someone who does yoga” and “has those elongated muscles.” So that’s were he started.

The diet was tough in the beginning. Ruffalo started with 21 days that consisted of one meal a day and two shakes. “No dairy, no meat, no caffeine, and no sugar,” Ruffalo said. He even had to lock himself away the first week! After that, he stated he began to feel really good.

Ruffalo transformed his own body so he could do the role of Bruce Banner/the Hulk under his own terms. Ruffalo’s body was used to soda and snacks, but doing the “Hulk Diet” benefited fans of the Hulk and also gave Ruffalo a healthy lifestyle.

Not-So-Powerful Legs

When you read superhero comics, it helps if you can suspend belief in all things practical and scientific. Comics - and any type of story medium - are meant to entertain, and The Hulk definitely entertains.

There’s one weird fact about The Hulk’s body that’s based on real science. As you know, everything about The Hulk gets stronger from head to toe: neck, arms, stomach core, legs, and feet. Now for the legs, something happens to them to augment the muscle. The enhanced twitching allows The Hulk to run extremely fast. He can get a strong initial burst of speed and maintain velocity for some time.

However, there comes a certain point when he gets running so fast that he is actually hurting his speed than gaining more. At this point, his legs become too strong. It’s a basic reason, really, that has to do with friction.

When The Hulk is at the peak of his speed in relation to his strength, his feet loose traction, thereby providing no extra speed to use.

This is one reason you see The Hulk jump so often: because he can get there faster if he does that instead of running there. See? There is some rational, scientific thought that went into The Hulk.

Fire-Proof Stomach

Robert Kirkman is the acclaimed writer of The Walking Dead comic. In the early days of that comic, before it became the powerhouse that it is today, Kirkman also wrote for other publishers, like Marvel. He took his talents to the X-Men, Spider-Man, Captain American, and more. Even if you’re a casual fan of The Walking Dead, the characters Rick Grimes, Glenn, Negan, and Daryl Dixon are easily recognizable from that comic or TV show.

Do you also know the name Eric O’Grady? Well, that was a notable character Kirkman created in issue #10 of his series, The Irredeemable Ant-Man. The art for #10 was from Phil Hester, Ande Parks, Val Staples, and Bill Crabtree.

This issue gave credence to the fact The Hulk had fire-proof insides, more specifically his stomach. O’Grady was aware that he couldn’t beat The Hulk fair and square, so Ant-Man flew into Hulk’s mouth and travels down to his stomach. At first, Ant-Man attempts to punch the stomach, but ends up almost breaking his hand. So Ant-Man tries a different tactic: burning The Hulk to ash from the inside. Ultimately, The Hulk was impervious to the flames.

His Pot Belly

Shifting over to the Marvel Cinematic Universe, you may not have noticed a few of the minor changes Joss Whedon wanted for Mark Ruffalo’s Incredible Hulk. Ruffalo did an extreme diet for 21 days to get “into shape” to play the Hulk, but there was nothing the actor could do for Whedon’s other requests.

Industrial Light and Magic did the special effects for The Avengers, including the CGI for the Hulk. They gave his Hulk a “muffin top.” Whedon told ILM that he “didn’t want somebody who was zero percent body fat.”

It was more importantly for Whedon to stick with the old TV show Hulk because that Hulk looked like he had “natural human skin.”

The special effects company had a blast constructing and animating the movie Hulk. It “gives us something to add all these secondary dynamics onto, because we can simulate with spring systems all the fat layers jiggling around and skin sliding on them.”

While Ruffalo probably lost enough weight to be the skinny Bruce Banner he saw himself as, but he still had to see himself as the slightly-pudgy (but more realistic) Hulk with a little dad weight around the middle. That’s the life of an actor.

Ghost Whisperer

One of the stranger facts about The Hulk’s body proves that it develops abilities to protect The Hulk in any situation, even emotional. Over time, he attained the power to see and talk to ghosts, just like Jennifer Love Hewitt in Ghost Whisperer. But how did The Hulk/Bruce Banner acquire this ability? The blame goes solely to Bruce Banner’s father, Brian Banner.

Bruce’s father was an addict and emotionally distant. Bruce suffered so much abuse that he was frightened of his father, even after Mr. Banner passed away. This fear manifested itself so deep in Bruce’s subconscious that the Hulk created the ability to see ghostly forms. This protects the Hulk and Bruce Banner in case Bruce’s dad comes back to mistreat him again.

That’s not the only reason the ability is strong. It also allows the Hulk to interact with Doctor Strange when he’s in his astral form. Doctor Strange tried to manipulate Hulk in this way, but the power surfaced so Hulk could defend against Strange’s powers. It’s not known if Hulk can control this power or if the power automatically does its job. There are very few non-magical superheroes or people that can do that, and the Hulk is one of them.

Heals in Seconds

If you had the power to heal, what would you do? Clearly, the Hulk enjoys this power during fights of any intensity. Wolverine has an impressive healing ability, but the Hulk’s is much, much faster. He most likely has the quickest healing power for any superhero in the Marvel catalog.

While superheroes can receive fatal wounds, the Hulk can absorb that same damage without worrying about losing his life.

While fighting Vector, the Hulk got his skin ripped off, leaving him with only exposed muscle. Minutes later, the Hulk regenerated his flesh to return himself to normal.

Probably one of the Hulk’s most worrisome weaknesses is adamantium. When the Hulk battled Speedfreek, the villain sliced the Hulk’s stomach open. So his insides wouldn’t drop out, the Hulk held the insides into his body, and minutes later, everything had healed just fine. Except his fingers got healed inside, the skin fusing around his fingers. The Hulk had to pull his fingers from the stomach and let it heal again, which again took a few minutes.

What’s might be stranger (and less explained) is the amount of mass Bruce Banner adds when changing to the Hulk. It might be one of the reasons that the Hulk enjoys accelerated healing, so his body can keep the balance between Banner and Hulk.

Hulk’s many faces in the MCU

Can you see a little of Mark Ruffalo in the movie version of the Hulk? If so, then that was by design. Joss Whedon wanted to ensure that Ruffalo was distinguishable in the Hulk. “Especially around the eyes,” ILM’s Jeff White said. “Even though the Hulk’s eyes are green, they really match Mark’s quite well.” Doing this change, the Hulk’s face from its canon appearance in The Incredible Hulk with Edward Norton.

The CGI team recorded massive amounts of movement data from Ruffalo, most importantly in the face. To humanize the Hulk, they put Ruffalo in a dome to capture movements and facial features as if Ruffalo was performing the feats of strength, like leaping between buildings, himself. The animators used Ruffalo’s expressions as “a great template so they could really tune those subtle performances to arrive at the final result.”

Whedon also wanted certain poses from the comic books used, but also gorilla photos. Combining the two gave “the Hulk a very cool look.” Plus, since the Hulk is so much taller than the rest of the Avengers, it was easier to use those gorilla poses to help ILM “compose the shots better as well.” White made sure to communicate that “Everything about the Hulk was grounded around the actor.”

Stress Levels

From hardcore fans of the Hulk, to casual readers of the comic and viewers of the Hulk TV show/movies, one thing is certain, most everyone knows that when Bruce Banner gets mad, he turns into the Hulk. “Don’t make me angry. You wouldn’t like me when I’m angry” is a commonly-quoted catch-phrase taken from the Hulk. Avid fans know it’s not just anger that makes the Hulk who he is. Stress levels also change Bruce into the Hulk.

When he becomes distressed - fighting, in frustration, emotional - Hulk will take over.

Now once in the latter form, the angrier Hulk gets the stronger he becomes. The body adapts to the level of stress Hulk is currently under. When there are high levels of anger (or stress), adrenaline pumps through Hulk’s body to dramatically increase strength. And guess what? This strength is apparently limitless. The Hulk has held up a 150-billion ton mountain and even broke Onslaught’s armor when the combined power of the other world’s heroes couldn’t do it.

This anger level only refers to the Green Hulk. The Red Hulk portrays different strength relative to how much gamma radiation he is exposed to. The more gamma radiation being focused at Red Hulk, the stronger he gets!

The Thunderclap

In the normal world, clapping your hands represents approval, praise, or sometimes sarcasm. In Hulk’s world, it’s one of the weirder powers he has. It’s called the Thunderclap.

It mostly seen in the comics, but you can catch it sometimes in the Marvel Cinematic Universe. It’s extremely powerful that it’s odd it’s not seen more in the movies. If you read many of the early comics, you knew this was one of the Hulk’s main, signature moves. Now days, it’s a lesser-known and used ability since the Hulk has so many other amazing powers.

The Thunderclap is a multi-level ability. On one hand, when the Hulk slaps his hands together, it creates such a concussive force it fells people huge distances away, hurting them immensely. If he controls the impact of his Thunderclap, he can also deafen enemies.

But the Thunderclap can also be used to help people. The blast is so amazing that it creates a mighty wave of wind that can put out fires. It’s such a strong ability that it could be used at any time to put villains in their place. But if it was used all the time, what would be the point of having the strength-related abilities - or even other superheroes?

His other Transformations

There isn’t just one Hulk. You might know the common version of the Hulk, also known as the Green Hulk. Stories exist where Bruce Banner never was exposed to radiation or where Banner and the Hulk were actually magically separated and exist as two entities in the same world. Two transformations are of particular note because although they are similar to the Green Hulk, their bodies are different: the Red Hulk and the Grey Hulk.

The Red Hulk is similar in terms of strength and speed, but not how retains it. As previously mentioned, the Green Hulk gets stronger the angrier he gets, the Red Hulk gets stronger the more gamma radiation he absorbs. This also includes cosmic radiation. Unfortunately, the Red Hulk can be mind-controlled, so villains take note.

The Grey Hulk is the original Hulk simply because of color printing issues; Stan Lee then changed the color to green.

However, the Grey Hulk is part of Banner’s personality that does the “bad things” Banner didn’t think he could do himself. This version was manipulative and didn’t care what others wanted, needed, or thought. The Grey Hulk isn’t as strong as the Green Hulk, but gets minutely stronger over time since the intelligence is clearly there and wouldn’t “lose control.”

Still, the Green Hulk is the one Earth would rather have.

Mind-Control Resistance

The Hulk can be considering a weapon of mass destruction. For the most part, he does good, fighting alongside the Avengers, though in some cases, the others annoy the Hulk. Nonetheless, he must be kept in check. Once he was sent to space because he was thought to be too dangerous for to be on Earth. The Hulk was tricked, so it wasn’t really his fault he ended up there.

It stands to reason that he must be able to withstand various types of mind control, otherwise this destructive creature could be used for evil. The Hulk has resistance to mind control for this basic reason. Would you want a villain as a puppetmaster to the indestructible and strong Incredible Hulk? The planet would be at the bad guy’s mercy!

Some theorize that the reason the Hulk can ward off the mental attacks of others is because he has multiple personalities living in his mind. You have Bruce Banner and the Green Hulk, of course, but there are other dimensions of Hulk ready to pop out at any moment. Because of that, not even the strongest of those with mind-control powers can’t control the personalities all at once. Therefore, no one can control the Hulk.

Internal Compass

Many superheroes have great powers of deduction. From Batman to Captain America, they seem to know where danger lurks and where to find the bad guys with minimal information. The Hulk is no different.

Bruce Banner had invented a special weapon called the gamma bomb, but during this time, an accident occurred and Banner was blasted with gamma radiation, allowing him to turn into the Hulk when stress levels get high. Surprisingly, this accident also gave the Hulk a great internal compass - except it’s very limited.

First, it allows the Hulk to find his way back to the radiation accident no matter where he is on the planet. The crater is large enough as it is and a simple satellite reading would provide the necessary location, but the Hulk’s internal compass is better and quicker. He can sense the original location in whatever dimension he happens to be in. Remember, the Hulk can punch his way into other dimensions with relative ease.

The Hulk’s internal compass seems to activate with precision in emotional distress.

In one comic issue, Abomination terminates Banner’s wife Betty and Bruce becomes so enraged that he’s able to find Abomination at the bottom of a lake. The Hulk would make a good camping companion, right?

Resilient Skin

The Hulk is strong, which aids in direct combat with bad guys or anyone who wants to attack him. But what about a defense? Well, that’s when his skin comes into play.

It is so resilient and thick that there’s barely anything on the planet that can penetrate it - except for adamantium , but we know that even if the Hulk is injured by that, he’ll just heal. Bullets, rockets, grenades, and anything else humanity can throw at him are useless. Even powerful villains are no match for the skin. It can handle major blasts and impacts from very powerful bad guys.

There are two other weird facts about the skin that are very interesting, though the ideas are used sparingly through the comics and movies. The first is that the skin can withstand both low and high temperatures. Remember when he was frozen in deep ice by Ice Man? When he got out, the Hulk had no effects from being housed in the cold for a long time.

Second, the skin can also withstand extreme pressures - like when he was sent to space several times with no protection or when he sunk to the bottom of the ocean floor.

No Sleep Needed

As mentioned before, there are basically multiple personalities residing in Bruce Banner/the Hulk’s head: Bruce Banner and the various Hulk forms. They all want out, but there came a point when Banner was able to control the Hulk manifestations at his discretion. This gave Bruce considerable advantages to go into Hulk form, except when returning to being Bruce, the Hulk expelled so much energy that it affected him as Banner and not Hulk.

Banner is aware of what the Hulk does, and the Hulk is aware of what Banner does. So it came as a shock to Banner that for the first time in The Incredible Hulk (issue #275), Bruce Banner felt hunger. The Hulk used so much energy, Banner needed to eat almost immediately after turning back to Bruce Banner.

Most importantly, the Hulk doesn’t need sleep. Bruce Banner needs sleep like the rest of the normal people, but the Hulk? No way.

The Hulk can go for a long time without going to sleep, but like the hunger, when he turns back into Banner, Banner must sleep.

In issue #275, Banner makes the comment that the Hulk appeared to be “capable of going for days - weeks - without sleep or sustenance.”

His Blood Can Heal Others

The Hulk is a champ when it comes to healing himself from various things that could hurt him. Bullets? No problem. Knives? Easy. Missiles? Nothing a few minutes won’t fix. But when it’s time for the body to heal, it’s hard to determine what actually heals the Hulk.

What we do know is that the Hulk’s blood heals others. For example, in Planet Hulk, the storyline follows the planet Sakaar, which is desolate and nearly uninhabitable. In a very literal way, Hulk’s blood heals the planet - causing a flower to bloom. This even makes him like a god and King of the planet. The Sakaarans feel that they now have hope for themselves and their planet.

The best case of the blood’s healing properties belongs to the very first issue of Savage She-Hulk. Jennifer Walters is shot and is most likely going to lose her life, so her cousin Bruce Banner makes the reluctant decision to do an emergency blood transfusion. Knowing that she would most likely become what he has become, he does the transfusion anyway.

Jennifer lives, but She-Hulk is born. She received the same abilities as the Hulk and can do just about anything he can.

Slow Fatigue Toxins

Of all the weird facets of the Hulk’s body that could be useful to normal humans, the best is probably the ability to not become tired. Our bodies need rest, naps, or sleep in order to recuperate form our daily activities. The Hulk doesn’t get tired as we do, namely because in the superhero form, he doesn’t produce what’s called “fatigue toxins.”

Now, Bruce Banner, because he’s regular human, needs sleep and rest as everyone else does - whether he chooses to do so isn’t as clear. As a scientists, Banner is always conducting experiments, coming to terms with his alter ego, and inventing new formulas and ways to fight the bad guys. Let’s just say he should get an average amount of sleep like the rest of us.

As the Hulk, his body is conditioned to handle extreme conditions for long periods of time without tiring.

Humans produce fatigue toxins over periods of time. Depending on your physiology, health, and conditioning, you could produce them faster or slower than the average human. The Hulk does produce them, but not at the same rate as people. It’s such a slow production, the Hulk can go for days fighting the same villain.

Immune To All Known Diseases

What kind of planet would we live on if everyone was protected against all diseases? Over-population is the first issue that should come to mind.

Some people are immune to certain diseases while others are not. While humans have the ability to create resistance to certain strains of infections and diseases, no one is completely immune to everything. Unless you shift over to the comic book universe and study the Hulk.

Since we know the Hulk can heal any injury or wound, it stand to reason that he can heal diseases.

It’s true: the Hulk is immune to all known diseases and viruses. This is handy because you don’t want one of Earth’s #1 defender to be knocked out by the common cold. T even be more specific, you learn in the comic issue #388 of The Incredible Hulk that he is even immune to HIV.

A previous sidekick who’s been diagnosed with HIV, Jim Wilson, is stabbed during a benefit show by Speedfreek. Bruce Banner tries to find something to stop the bleeding, but knows he could be exposed to the virus, so he changes into the Hulk and rushes his friend to the hospital for treatment. As the Hulk, he didn’t have to worry about contracting the disease.

His Eyeballs Are Just As Strong

If there’s one part of the body you wouldn’t expect to be strong, it’s the eyeball. It’s a soft, squishy orb that is integral to everyday life in terms of vision. Those who can’t see are superheroes in their own right.

There are no obvious physical weak spots on the Hulk that one can get a cheap shot in. If you expected a bad guy or another to try for the eyes and win, you’d be mistaken.

Valkyrie has an enchanted blade called Dragonfang and in Incredible Hulk, issue number 207, writer Len Wein gave Valkryie a chance to prove that the Hulk is weak in the eyes. Valkryie swings the weapon and slashes Hulk’s face through the eyes. Hulk takes the hit, then when the sword moves away, Hulk appears unharmed. You can imagine him laughing inside, thinking, “Is that all you got?”

Now what’s important is that Hulk takes the sword and attempts to break it, but he can’t. For all of Hulk’s strength, he can’t harm the Dragonfang, as far as we can tell. If Dragonfang can’t even hurt the Hulk’s eyes - as strong as the sword is - what possibly could hurt the Hulk at all?

He Could Be Immortal

Superheroes, while powerful and having numerous abilities to make us mere mortals jealous, are fallible, with physical weaknesses that could destroy them. But the Hulk is a different breed of superhero. In fact, the Hulk could quite possibly be immortal. The evidence is provided in a one-shot comic written by Peter David, titled Hulk: The End. Artists on this issue were Dale Keown, John Livesay, Joe Weems, and Dan Kemp.

The story is in an alternate universe in which nuclear devastation left Bruce Banner and his alter ego the last pieces of humanity alive. Oh, and there are mutant cockroaches that eat Hulk’s body constantly to the bone, but since we know he heals within minutes, the Hulk is fine in this alternate universe.

Bruce Banner tells us that he might have died hundreds of years ago, but his Hulk half can eat just about anything and transfer it to energy. If you happen to read this one-shot, you’ll notice that the Hulk doesn’t look like he’s aged one bit. The story itself suggests that the Hulk has decelerated aging. It must slow down so much that the Hulk can be considered immortal, or at least capable of living for thousands and thousands of years.

What facts about the Hulk’s body do you find weird? Let us know on the comments!