The X-Men are one of the most effective superhero teams in all of Marvel comics. Notorious for their battle-readiness, most villains hope to avoid facing this mutant team. Often times the X-Men know just how they can combine their many powers in specific ways to defeat all different kinds of enemies.

This team's cohesiveness didn't develop overnight. Thanks to their advanced Danger Room, the X-Men are able to train 24/7 against lifelike robots and holograms of their many enemies. While this Danger Room has greatly helped the X-Men over the years, it also has many dark secrets. Here are the top ten secrets about the X-Men's Danger Room, revealed.

10 10. The Danger Cave

Danger Room Sentinels

After the X-Men lost the Danger Room due to mitigating circumstances, the mutant team resorted to using a "Danger Cave." Much like the Danger Room, this new Danger Cave had hologram technology that helped the X-Men simulate battles and work on their fighting skills.

Unlike the Danger Room, however, the Danger Cave only had holograms that re-enacted battles form the X-Men's history. This included outer space battles like Broodworld and Planet X, along with fights against powerful enemies such as Onslaught.

9 9. The Killing Zone

Wolverine and Gambit training in the X-Men's Danger Room in Marvel Comics.

In the alternate universe of Age of Apocalypse, the X-Men had no Danger Room. Instead, the X-Men had an entire training facility. Located in Mount Wundagore, this training facility was called the Killing Zone.

After many years of training several generations of X-Men, the Killing Zone was destroyed by one of Apocalypse's lieutenants, Nemesis. After its destruction, the mutant Dazzler became the go-to trainer for the X-Men, replacing any need for a training facility.

8 8. Gift From the Shi-ar

Danger Room scene from X-Men The Last Stand

A noble race of aliens, the Shi'ar came into conflict with the X-Men several times early in the team's history. As time went on, the X-Men and Shi'ar Empire came together to become allies.

The original Danger Room was quite crude in its design. Once filled with traps such as collapsing walls and motion-activated flamethrowers, this mutant training facility was in desperate need of an upgrade. Hoping to repay the X-Men for their help, the Shi'ar Empire gifted a brand new Danger Room to the X-Men, powered by their advanced alien technology.

RELATED: X-Men: The 10 Most Dangerous Members of The Shi’ar Imperial Guard

7 7. Gained Sentience

Danger Robot of the X-Men in Marvel Comics

In secret, the artificial intelligence of this new Danger Room slowly began to gain self-awareness. Filled with rage, this new sentience first convinces a young mutant named Wing to kill himself. It then uses its technological tools to take control of a Sentinel robot.

While the X-Men are distracted by the Sentinel's attacks, the AI creates a physical body for itself. Deciding to take on a female form, the Danger Room then decides to name itself Danger.

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6 6. Tried to Kill Professor X

Danger from the X-Men

The first person Danger wishes to kill is Professor X. It turns out that he had known about the training room's intelligence for some time, but decided to let it suffer rather than set it free.

Then, when Danger finally confronts the Professor face to face, it was revealed that he did in fact try to set her free. Unfortunately, due to the fact she is made up of Shi'ar technology, Xavier wasn't sure which cords he could cut to set her free and which cords being cut would essentially lobotomize her. Out of compassion, he decided to keep her alive despite her being a potential threat. Because of this, Danger forgives the professor and ends her crusade against the X-Men.

5 5. Joined the X-Men

After reconciling with Professor Xavier, Danger accepts an offer to join the X-Men. The X-Men professor continues to work on fixing Danger until her apparent suffering subsides. This increases her trust in the team and leads to her becoming a valuable member.

As an X-Man, Danger is able to add much to the team. She not only has a wide variety of technological powers, but also vast knowledge about mutants and their abilities. Danger uses this knowledge in order to help some of the X-Men develop their abilities, in much the same way she did when she was still simply a training room. One example of this is when she helps Rogue learn to fully control her powers.

RELATED: X-Men: The 10 Most Confusing Things About Psylocke

4 4. Jean Grey School for Higher Learning

jean-grey-school

After the Schism event, the X-Men were split into two groups. Half of them followed Cyclops, hellbent on a mutant revolution, while the other half followed Wolverine, hoping to uphold the legacy of the recently passed Charles Xavier.

Since the X-Mansion had been demolished, Wolverine and his team of X-Men decided to rebuild it, naming this new academy the Jean Grey School for Higher Learning. Instead of simply one room equipped with Shi'ar Danger Room technology, this time the entire school has it. This gives the school state of the art defense systems all over, designed to protect the students from any incoming threat.

3 3. Blackbird

After the original five X-Men are brought into the future by the X-Man Beast, they eventually decide to set off on their own as a separate X-Men team from either Cyclops or Wolverine's forces.

This team needed a means of transportation and chose an interestingly upgraded version of the Blackbird. The longtime jet-plane of the X-Men, at first glance it would appear there is nothing special about this version. However, this new Blackbird had the Danger AI embedded within.

2 2. X-Men Database

15 Things Everyone Gets Wrong About The X-Men

The most dangerous thing about the Danger Room is its knowledge of the X-Men's powers. One of the main reasons that Professor Xavier was so afraid of setting the AI loose was because of this knowledge.

Danger is aware of all of the X-Men's strengths and weaknesses. Anyone possessing this knowledge could easily dispatch of the mutant team. The mutant team better hope no nefarious forces ever get their hands on the Danger Rooms database.

1 1. What If?

ultron

In an alternate "What If?" universe, Danger Room escaped the X-Men. After crafting a body for herself, she "married" Marvel's other more famous AI, Ultron.

After joining forces, these two robots became the most formidable force in the galaxy. Not only did they manage to conquer Earth, but the two robots also traveled into space to conquer the Shi'ar Empire as well. Heroes of the mainstream universe better hope these two beings stay as far away from each other as possible.

NEXT: X-Men: 10 Times Iceman Earned His Status As An Omega-Level Mutant