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.
 * Huge 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, 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 (イグドラシル)
 * En:.

Alias used while in the Real World in Digimon Next.
 * Norn Mikihara (美樹原 ノルン)
 * . Beings from who are bound to.
 * Ja: Mikihara (美樹原). Japanese surname that means "beautiful tree field". Likely a reference to the mythological tree.

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  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 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 binding 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 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.