Yggdrasil and its attendants were normal members of their species before being turned into cyborgs as a Pokefutures experiment, before being put into stasis and having their data wiped before the PEFE acquired PEFE Island.
Yggdrasil awakened after Veðrfölnir and Giant Braviary were defeated, and ended up fusing with a module in the center of the facility. It immediately started growing giant vines throughout the building so the group there had to take a detour through the bowels of PEFE Island to reach it, learning about both it and the Alakagross Civilization thanks to Team Nova and Sentinel. Upon reaching it the J-Team members did battle with it, only to find that it had a quite powerful healing factor. After Draca used Fire Blast on the tree, Tagg figured out using Aura Sense that its healing factor was being powered by a mass located somewhere in the upper trunk.
While trying to destroy the mass, the group ended up having to fight the four Sawsbuck guarding it, while Shadow worked to reveal the mass. One of them ended up dying once Chrome knocked it off the tree with an Ice Punch, while another was frozen by Icicle's Ice Beam before being shattered by Pica ramming it as she rocketed up. Chrome then used an Ice Punch to kill another, before the last fell to Draca's Fire Blast, Sentinel's Fire Punch, and Tagg's Aura Sphere. The mass was then destroyed by a combination of various attacks.
Enraged, Yggdrasil tried to kill the group with larger vines, but was prevented by doing so by the timely arrival of Vanilluxe and Audilith, followed by the rest of Tagg's mons. Together, they managed to finish off Yggdrasil, Muddy and Gaia doing the coup de grace by using Hydro Cannon and Frenzy Plant respectively. Upon its defeat, Xatu and a number of other teleporters transported it to an analogue of the Challenger Deep where its explosion wouldn't harm anyone. Before this happened, it let everyone who had freed it know its thanks.
Powers and Abilities
So large that it was incapable of moving, its tree being roughtly as tall as the dome was high, Yggdrasil had a powerful healing factor strong enough to ignore a Heal Block, and the ability to send out quickly growing vines that healed as quickly as it. The four Sawsbuck had the ability to merge with Yggdrasil's tree in order to more quickly travel up it.
- Yggdrasil is based on the world tree from Norse mythology, and its Sawsbuck attendants are based on Dáinn, Dvalinn, Duneyrr and Duraþrór, the four stags that live in Yggdrasil's boughs.