Yggdrasil, the World Tree
The original Yggdrasil was impossibly wide, incalculably tall, and other measurements as well. It was the site of the Tree City of Wakah-Chan, as well as being the residence of the Elder Hekate. The topmost branches and leaves were not able to be seen, towering high into the clouds, wreathed in wisps of white cloud, and the roots that tunneled deep into the core of the Earth and also burst from the ground like clawing fingers that were as tall as cars. It housed countless ecosystems from above the tree to below it. The tree itself was gnarled and twisted, its bark deeply etched with cracks and lines. Long vines, like huge pipes, wrapped around the tree and dangled down from the branches. There were hundreds of windows cut into the bark, with lights flickering in the rooms beyond.
Appearance
The interior of the tree was hollow. From just inside the entrance, a person could look straight up to where wispy clouds gathered inside of the tree. A gently curving staircase curled up along the inside of the trunk, and every few steps brought them to an open doorway spilling out light. Bridges of branches streched from one side to another. Branches could even grow to the size of sixty feet wide, if not more. Dozens of tiny waterfalls spouted from the walls and splashed down onto the floor far below, where the water gathered in a huge circular pool that took up most of the foyer. The interior walls were smooth and unadorned, except from the twists and knots of vines that broke through the surface. The Nathair are the winged guardians of Yggdrasil.
The Second Yggdrasil
When the original Yggdrasil was destroyed, Hekate and Odin, both deities of magic, managed to grow a second Yggdrasil, with Hekate taking up residence within once again. The seed from which this tree grew was salvaged from the original Yggdrasil after the fall of Danu Talis.This tree was the place where Sophie Newman was Awakened by Hekate. The topmost branches of Yggdrasil extend far into the Asgard Shadowrealm, while its root went down to the Niflheim Shadowrealm and a formidable monster, Nidhogg, was trapped there by its roots, which were believed to have been imperishable. The second Yggdrasil was killed by Dr. John Dee, when he plunged one of the Four Swords of Power, Excalibur, into the tree. Excalibur froze Yggdrasil, then Hekate, ultimately shattering them both.