King Drasil

Yggdrasill is a 9000 Digimon. It is the mysterious host computer who rules over all of the "Digital World" on one Server of the Network. Its primary form is that of the Server Tree, an enormous, sacred tree. Bagramon replaced its lost eyes and right half of its body, taken from it by God, with wood cut from the sacred tree. It has created an avatar in the form of "Yggdrasill_7D6", whose body has many unidentified details, and Shakamon is rumored to be the being closest to Yggdrasill in the Digital World. It gathered the Royal Knights in order to manage the world, and it seems that its will will eventually lead the Royal Knights to cross Servers to the Digital World: Iliad Server and meet the Olympos XII face-to-face.

Attacks
 * Crystal no Hahen (クリスタルの破片): Fires crystal shards.
 * Kyodaina Crystal (巨大なクリスタル)Fires a gigantic crystal.
 * Jikoshūfuku (自己修復): Uses a self-repair ability.

Design
Yggdrasill's design, showcased in Digital Monster X-Evolution, is a pristine crystalline sphere on a similarly-formed.

The Server Tree's design is derived from the mythological, an immeasurably large tree which supported the various worlds in. Although it resembles a mundane tree, the ivy growing over it are s, and its wooden trunk is inlaid with, and it contains chambers for the Royal Knights to gather. Several of Yggdrasill's crystals act as its security system, and possess the ability to fire beams of energy or absorb and reflect attacks.

Yggdrasill_7D6's design is that of formless, crystalline being, with countless ivy-like vines growing from it as on the Server Tree.

Norn's design is derived from the mythological s, with her bound outfit being based on fashion, while her freed outfit is based on  fashion with details drawn from Yggdrasill_7D6's design.

Etymologies
Yggdrasill's name is derived from the mythological. The name of its main avatar, Yggdrasill_7D6, is derived from the representation of "2006", the year of its debut, while the name of its other avatar, Norn, is derived from the mythological s who tend to Yggdrasill. Its alias as the "WIZ 9000 Computer" and its "9000" type are derived from WiZ Co., Ltd., who developed the and Digimon Virtual Pet with Bandai. The Server Tree's name is derived from its status as the Digital World's Server.

Digital Monster X-Evolution
The original Digital World was cultivated and populated with Digimon by Yggdrasill. However, the continuous multiplication of Digimon left the computer unable to handle the data load, resulting in an apocalyptic event known as the "Digital Hazard" that saw the Digital World begin to collapse. Yggdrasill initiates "Project Ark," hand-picking a small number of Digimon to survive the catastrophe and transplanting them to a new Digital World it created. However, Digimon who survived the death of the old world by way of the mysterious "X-Antibody" appear in this new Digital World, disrupting Yggdrasill's plans.

In order to move Project Ark into its second phase—the complete extermination of the Digital World and all Digimon life—Yggdrasill creates an experimental being,, from whose data it creates a vast army of , as well as its personal protector, , who later becomes. Discovering Yggdrasill's true intentions, the Royal Knight turns on it, and after becoming an "X-Digimon" himself, he sends Dorumon to his comrades,  and, in an attempt to bring an end to the fighting.

In the Royal Knights' stronghold, Dorumon is revealed to be, the legendary leader of the Royal Knights. This information is enough to convince Omnimon to face Yggdrasill, and he goes with Alphamon to seek counsel with his master, defeating DexDorugoramon and Dexmon, who bar their way. As this is happening, Yggdrasill initiates the second phase of Project Ark, and the Digital World begins to die as the DexDoruGreymon sweep across it, reality crumbling in their wake. To stop the computer's scheme, Omnimon—transformed by Alphamon's X-Antibody—strikes his master down with his "All Delete" attack, destroying Yggdrasill and allowing the Digital World to be reborn.

Later, Omnimon and Gallantmon speculate on Yggdrasill's intentions. For all that it has done, a reason remains unclear to both Knights—but in the end, Gallantmon believes that Yggdrasill was, just as all Digimon were, fighting against its own inevitable destruction.

Digimon Data Squad
King Drasil is first mentioned by, who, ten years before Marcus joined DATS, told Dr. Spencer Daman of King Drasil's existence. Spencer and Merukimon departed, with the former stating that he would seek out King Drasil himself.

Years later, it seemed that Spencer had found King Drasil with 's help. After defeating Craniamon, King Drasil brought up the Server Tree. Unfortunately, Kurata's unprovoked attack sent Spencer to prison to await trial. Spencer pleaded to be given one more chance on his life which King Drasil granted, only to be shocked at the news of Merukimon's deletion at the hands of Gizumon-XT. This incident convinced King Drasil that humans are a threat to Digimon, ordering the Royal Knights to seize Spencer. But BanchoLeomon managed to escape with Spencer's soul in his body. But this didn't go unnoticed by King Drasil, who possessed Spencer's body to see through human eyes and warned BanchoLeomon not to tell anyone or he'll destroy Spencer's body. By the time Marcus and his comrades sought King Drasil in order to try and find a solution with him, they are encountered by King Drasil's cohorts, the Royal Knights, and eventually King Drasil himself—in the body of Spencer Damon.

Using Spencer's body, King Drasil ordered the destruction of the Human World in order to save the Digital World, sending his Royal Knights out across the globe to destroy it. Marcus resolved to discover the truth of what his father had become, and embarked on a quest to find King Drasil again. Once he found his "father", Marcus fought him until BanchoLeomon arrived and revealed the story about his link with Spencer before sacrificing his life for ShineGreymon to take out Spencer possessed by King Drasil. But it was in vain as King Drasil assumed the form of its Yggdrasill_7D6 avatar, and flew off to the real world. Once there, he easily defeated the Burst Mode Digimon. Upon the Royal Knights arrival, King Drasil saw that even its own devotee's were beginning to doubt its sovereignty as lord, evoking its rage upon them. By the time Marcus and the gang arrived to fight him in the final decisive battle, King Drasil revealed that it was actually the computer which was designed to control all lifeforms in the Digital World at its will. Because of its observations of human-Digimon interaction, it desire to start over and reset the universe and began to turn any Digimon holding up the Digital World back into Digi-eggs. The Royal Knights helped Craniamon keep the Digital World from colliding with the Earth; King Drasil calculated a very small chance of success. But his Knights tell him all beings desire to live, which the simplistic computer couldn't comprehend.

Agumon underwent a Burst Digivolution, blasting a massive hole in King Drasil. Yggdrasill Core, a crystalline figure with a female appearance, shot out of the robotic body and Marcus promptly punched it in the face, shattering it and finally defeating it. Recognizing its defeat and the real power of the combined efforts of Humans and Digimon, King Drasil's last act was to bring Spencer back to life before entering a state of hibernation saying, "I would like to see how things turned out".

Unfortunately, due to King Drasil's defeat, the Digital World was left leaderless, so the DATS Digimon resolved to return to rebuild the Digital World. Marcus came along and he and Agumon became peacekeepers.

Digimon Next
Yggdrasill is the God of the, a highly complex computer. In order to investigate the relationship between humans and Digimon, it sent its conscience to the human world in the form of Norn, a young girl. With Norn gone, invaded the System World and interrogated Yggdrasill's body, and the two both agreed that a revolution was needed to correct the injustices upon Digimon caused by humans. Barbamon fused with Yggdrasill's body to become its new avatar, and began enacting their plan, including bindingdown Norn's true self with literal chains when she returned. However, once Tsurugi and Yu digivolve their partners into the Arbitrators, Barbamon and Norn reveal the truth of the matter. Barbamon attacks the heroes, but when Tsurugi realizes overcomes his rage towards Barbamon and focuses on his goal of protecting all the Digimon of the Digital World, VictoryGreymon finally responds and slays the Barbamon-Yggdrasill hybrid, which awakens as it dies.

Yggdrasill's conscience was sent to the Real World to learn what Digimon mean to humans, and took the name "Norn Mikihara". A kind girl, she befriended, , , and , but was imprisoned by when she returned to the Digital World. She keeps the Anti-God Devices Digimon Twin to give to Tsurugi and Yu when they are ready. When Barbamon and Yggdrasill_7D6 are defeated, Norn becomes the true Yggdrasill and a new goddess for the. She uses her powers to open the portal to, and, at the end, promises Shou to be the best goddess she can be.

Digimon World Dawn and Dusk
mentions Yggdrasill in the "Search the Digiarea" Quest. When he has the Tamer Organizations, including Koh/Sayo, at his mercy, he taunts Yggdrasill by claiming that his Project Ymir will overwrite the Digital World.

Digimon World:Re:Digitize Decode
After being sealed inside the Infinity Mountain simulation, Yggdrasill is reactivated in order to be the responsible of repairing the Digital World from the damage caused by the sub-lifeform Vitium. To do that, Yggdrasill reactivates the X-Program, causing many Digimon in the island, including the Royal Knights Gallantmon X and Omnimon X, to wonder why Yggdrasill repeated such tragedy again.

As the protagonist (Taiga or Rina, player's choice) goes to the Infinity Mountain to investigate those events, they meet Yggdrasill in the 12th floor. Yggdrasill forces DoruGreymon to evolve into Dexmon in order to carry on the Project Ark, to restore the Digital World and wipe out the humans, that Yggdrasill threats as "the noise who disturb the balance of the world". After Dexmon is defeated, the player must fight Yggdrasill to stop the X-Program. Yuuya helps the protagonist to defeat it, as he states that he dislikes Yggdrasill.

Yggdrasill reappears at Lv. 100 on the 100th floor of Infinity Mountain, as the most powerful boss in the game. This time, Alphamon appears to help the protagonist to defeat Yggdrasill, as he wants to settle up with it for having been transformed him into Dexmon.