Fimbulwinter enveloping the Earth.
Fimbulvetr (or Fimbulvinter), commonly rendered in English as Fimbulwinter, is the immediate prelude to the events of Ragnarök in Norse mythology. It means "great winter" and is a harsh unforgiving winter that will "grip and throttle" the Earth.
Overview[]
Fimbulwinter is the harsh winter that precedes the end of the world and puts an end to all life on Earth. Fimbulwinter is three successive winters, when snow comes in from all directions, without any intervening summer. Then, there will be innumerable wars. Fimbulwinter will occur in response to Baldr's death at the unintentional hands of his own blind brother Hodr who was under the influence of Loki himself.
It is revealed that Fimbulewinter was caused by the Glacier Stone, one of the Ab Initio Artifacts, wielded by the Frost Giants who cover the Earth in an unforgiving winter in celebration of Baldr's death. This was also a sign for them to make preprations for their final war against the Æsir gods. Because of it being magical in nature, Fimbulwinter over time caused curses, magical items/weapons, and other blessings to weaken across the Nine Realms, some more than others, or disappear entirely.