Aesir

The Aesir, known as Polar Gods in the OCG and anime, are mysterious monsters used by Team Ragnarok in Yu-Gi-Oh! 5D's.

In the anime, the "Aesir" are currently the only DIVINE-Attribute, Divine-Beast-Type Synchro Monsters ever seen, as well as the first DIVINE-Attribute monsters of any kind since the Egyptian Gods. However, their Attributes and Types were changed in the OCG. "Loki, Lord of the Aesir" is a DARK Spellcaster, "Thor, Lord of the Aesir" is an EARTH Beast-Warrior, and "Odin, Father of the Aesir" is a LIGHT Fairy. Each member of Team Ragnarok possesses one of these cards. Dragan held "Thor", Brave held "Loki" and Harald held "Odin". In the game, these cards are strong united, but are weak when they stand alone.

History
The three cards are named after the top three Gods in the Norse mythology pantheon. The God King, Odin, The God of Thunder, Thor and the half-giant God of trickery, Loki. In Norse mythology, these 3 gods are said to form part of a huge battle known as Ragnarök in which they will die. They can be considered Polar Gods due to the prelude of Ragnarök known as Fimbulvetr, which is a time of three winters with snow coming from all directions without any summers between. During this time, there will be wars, brothers killing brothers and eventually all life on Earth will be destroyed. They can also be considered Polar Gods due to their association with Scandinavia and Nordic Countries (located within Scandinavia) which itself is located north extending to the Arctic Circle.

In the anime, these cards were found in caves with tree roots surrounding their interior by the duelists they engraved the Rune Eyes upon. The roots in these caves are probably an allusion to the world tree of Norse Mythology, Yggdrasil.

The name "Aesir" is essentially meant to be the term Æsir, the term used to identify an entity from Norse paganism, which includes all three of the Polar Gods' original gods. This is because the grapheme "Æ", a ligature, is formed from "A" and "E" - and in places where the grapheme is either difficult to use or otherwise unsuited, the two-letter set "Ae" is often used as a replacement. (It is notable that this replacement would be improper for languages where "Æ" is a letter; one such language is the language where the term "Æsir" comes from, Danish).

Powers (anime)
The powers of these gods rival that of the Crimson Dragon. When "Thor" clashed with "Red Dragon Archfiend", both monsters emitted a strange energy pulse, wreaking havoc around the dueling arena and drastically upsetting the weather outside the stadium.

These cards also protected Team Ragnarok and their memories from the Three Emperors of Yliaster's alterations of the timeline.