Duel Monster Spirits

Duel Monster Spirits, Duel Spirits, or what are now known as Duel Monsters is the name given to the creatures who's remnants inspired Maximillion Pegasus to create the popular card game of the same name. They live primarily in the Duel Monster Spirit World.

They have their own societies in each section of the spirit world (sections which are later explained by Yubel to be entirely different dimensions), however the majority appear to be allies of each other and human world, although there have been conflicts between the spirits of some dimensions, such between DARK attribute, FIEND type monsters and LIGHT attribute, Fairy type and Dragon type monsters among others. The Duel Spirits of some section are allies of the human world as many ancient societies such as Atlantis, Egypt and the People of the Stars. The Earth has been both aided and plagued by both good and evil spirits.

One section of the spirit world appears to be based of mostly Fairy and Dragon type monsters although Dark Magician Girl appeared to be the leader of them. Her presence in this place may indicate other Spellcaster type monsters such as Dark Magician also live. The most notable Duel Spirits from this area are the Legendary Knights of Atlantis, Timaeus, Critias, and Hermos who are it's guardians. According to Dark Magician Girl, the spirit world has existed as long as mankind has existed.

Another section is Neo-Space, which appears to consist mostly of Alien-themed monsters such as Elemental Hero Neos. This is a separate dimension and was once ruled by the King of the Duel Spirits, the father of the Supreme King. It is also the original home of Yubel.

History
Duel Spirits have played a pivotal role in human history dating back at least ten thousand years. Humans somehow found a way to summon them here the human world using magic and spells. The Ancient Egyptians sealed their spirits (or the means to summon them) in stone tablets. These tablets resembled duel monsters cards and later inspired Maximillion Pegasus to create the game. In doing so, Pegasus sealed the duel spirits (or means to summon them) in the cards, similar to how they were sealed in the tablets. However, they are only truly summoned when magic forces are involved or when they are involved with certain individuals. Psychic Duelists may be people who are able to summon spirits and cause real damage, although at the moment the origin of their powers is unknown. There is a theory which states that the Zero Reverse incident reawakened the powers to summon spirits in certain individuals.

Back in the times of Atlantis, the spirits came to the aid of Ironheart, Chris and the survivors of Atlantis after it's king, Dartz, corrupted and brainwashed by the Orichalcos, began a conquest to destroy all life on Earth to recreate it. They sent a huge army against Dartz's Orichalcos soldiers and the Great Leviathan in the Battle of Atlantis. Neither side was vitorious, Atlantis sank into the ocean depths and the Duel Spirits were sealed away until they be needed again.

Around that time the Crimson Dragon and it's servants the Signer Dragons battled the evil entity called Scar-Red Nova to exhaustion. It was only through the help of a Legendary Signer that Scar-Red Nova would be defeated and sealed away into the Earth and become the first of the Nazca lines, thus becoming the first Earthbound Immortal. Signers are beings who possess the ability to summon their specific signer dragon from the spirit world.