
The sword severed the thick roots of the World Tree in the spring and, at that moment, Jötunheimr lost the blessings of the World Tree, becoming a desolate world of frost. He then stole the Holy Sword Excalibur, forged by the blacksmith god Völundr, and threw it into Urðr's Spring at the center of Jötunheimr.

Once upon a time, the king of the frost giants in Niflheimr, named Thrym, transformed into a wolf and infiltrated Jötunheimr. The dungeon can only be reached with the help of flying beast-type Evil Gods, as none of the fairy races can reach fly to the dungeon by themselves due to their flight being greatly limited or disabled within dungeons. The entrance to the dungeon is a terrace that protrudes from the top of the pyramid. The rooms within the castle are riddled with various complicated passageways, puzzles involving the use of levers, gears or stepping switches to unlock access to the next area.

Due to the shape of the dungeon, the lower floors of the dungeon are smaller than the top ones, with the 3 rd floor being around 70% of the 2 nd and the 4 th consisting of mostly the boss room. Several luminous points are trapped within the icicle, giving the illusion of a gigantic eye blinking majestically, while, internally, it is divided into 4 sections with a myriad of rooms and passages being dug in the ice.

The base of the pyramid is about 300 meters on each side and its height is about 300 meters as well. Thrymheim is a large inverted pyramid-shape ice structure that is held about 1000 meters or more above the Great Void by the branches of the World Tree that form a net.
