Marvel comics are filled with the mysterious unknown. Within many different stories, Marvel showcases the mysterious and terrifying. Such an example would be the many alien worlds and planets that the Marvel characters like to visit.

Another good example of a strange world from Marvel is the Negative Zone. An alternate reality frequented by many of Earth's mightiest heroes, the Negative Zone is one of the oddest locations in Marvel lore. Although its history within Marvel is long, there isn't much that the average comic book fan actually knows about the Negative Zone.

Here are the top ten things Marvel fans never knew about the Negative Zone.

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10 10. Discovered By Mr. Fantastic

Although this dimension had seemingly existed for all of time, it wasn't until Reed Richards came around that it was actually discovered by a human. While looking for an alternate means of dimensional travel, Reed Richards stumbled upon the Negative Zone.

After doing so, Reed began to study this new alternate dimension. Since then, the Fantastic Four have traveled their many times, battling all kinds of foes and conducting all sorts of different experiments.

9 9. Blastaar

Fantastic Four villain Blastaar grimacing in Marvel Comics

A long-time villain of the Fantastic Four, Blastaar actually hails from the Negative Zone. During one of Reed Richard's many trips to the Negative Zone, Blastaar spotted him and decided to follow Richard's back to his home dimension.

In the years since then, Blastaar has tried many times to conquer the Earth. Each time he is defeated, most often by the Fantastic Four, and sent back to his home dimension. Although Blastaar and another FF villain, Annihilus, are both from the Negative Zone, they are actually enemies.

8 8. Annihilus

Annihilus demonstrates his rage

One of the most powerful villains of the Fantastic Four, Annihilus is another enemy that has long lived within the Negative Zone. Much like Blastaar, Annihilus is a conqueror of planets that lives within this dark, alternate dimension.

Within the Negative Zone, Annihilus has a powerful weapon called the Cosmic Control Rod. This deadly villain has actually used the Control Rod to take complete control over the entire dimension. After conquering the Negative Zone Annihulus set his sights on conquering Marvel's mainstream universe.

7 7. Captain Mar-Vell and Rick Jones

For a time, the superhero Mar-Vell and the adventurer Rick Jones became bonded to one another. While they were bonded, one had to stay in the Negative Zone while the other was in the real world. Once the Earthly one of the two clanked his bands together, the two beings would switch places.

For a time, Captain Marvel operated this way, switching places with Rick Jones whenever he needed to save the day. Eventually, the bond was removed and both men were able to travel to the real world at the same time.

6 6. Spider-Man's Negative Zone Costume

PS4 Spider-Man Negative Zone Suit

Although the web-slinger doesn't often visit alternate dimensions, during one of his many adventures he did manage to find himself within the Negative Zone. During his visit, Spidey found a new costume that granted him new abilities.

After leaving the Negative Zone, Spider-Man brought this new costume with him. The crimefighter could now use his new suit to merge with shadows and become completely undetectable.

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5 5. Carnage Symbiote

Not only did Spider-Man manage to visit the Negative Zone, one of his greatest enemies, Carnage, visited as well. After Cletus Kasady lost his symbiote suit, he later found himself transported to this alternate dimension.

While exploring this new dimension, Cletus ran into a new symbiote suit. As it bonded to Kasady, it was revealed that this was, in fact, his Carnage symbiote. It's almost as though fate itself wanted this crazed serial killer to get his powers back.

4 4. Prison For Villains

During the Civil War event, Tony Stark and Reed Richards designed a very special prison for his enemies, many of which included Marvel heroes on the other side of the conflict. This new prison, dubbed "Project 42," was built within the Negative Zone. Even if any of the prisoners managed to escape, they would still be in an alternate dimension.

Although this was a great idea, Captain America was able to outsmart Stark. It turned out that Hulkling had infiltrated Iron Man's team as a mole for Cap's team. Hulking, on Cap's orders, released all of the heroes and villains from their Negative Zone prisons, allowing them to rejoin the fight on Captain America's side.

3 3. Negative Emotions

Howard in the Negative Zone Deadpool The Duck

One of the most strange effects of the Negative Zone is the ones it has on human emotions. While in this alternate dimension, many of a person's most negative emotions are brought out. Depending on who the subject is, these effects can be either quite drastic or quite minimal.

Not all inhabitants of the Negative Zone feel these effects, but newcomers are clearly more susceptible to it. They can feel fear, sadness, loss of hope and even great panic.

2 2. The Crossroads of Infinity

A massive vortex within the center of the Negative Zone, there are many different theories surrounding the Crossroads of Infinity. For much time it was theorized that anyone caught within the vortex would be sent into another dimension. This theory was then tested when Doctor Doom decided to send his mortal enemies, the Fantastic Four, within the Crossroads.

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As the Fantastic Four traveled through the Crossroads, they were flipped through several different parallel dimensions. Once their journey was over, the superhero family was able to safely travel home. That trip, however, is one they are not likely to go on again any time soon.

1 1. There is Only One

One of the most interesting facts about the Negative Zone is that there is only one. Although the mainstream Earth has an endless number of alternate reality versions of itself, the Negative Zone is a completely unique dimension without any alternatives.

This is evidenced by the fact that many heroes from alternate Marvel world, such as the Ultimate Marvel universe, have at times traveled to the Negative Zone. During these trips, it is made explicitly clear that the Negative Zone they are visiting is the same one Reed Richard's discovered in the mainstream universe.

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