Ragnarök, also known as the Twilight of the Gods, is a major event first prophesied by the Jötunn Gróa that foresees the ultimate battle that results in the death of many gods, including Odin and Thor, as well as the "rebirth" of the world through submersion into water. Kratos and Atreus are also mentioned in the prophecy, as being the center of everything.
In Norse mythology, Ragnarök is a series of future events, including a great battle, foretold to ultimately result in the death of a number of major figures (including the gods Odin, Thor, Týr, Freyr, Heimdallr, and Loki), the occurrence of various natural disasters, and the subsequent submersion of the world in water. Afterward, the world will resurface anew and fertile, the surviving and returning gods will meet, and the world will be repopulated by two human survivors, Lif and Lifthrasir. Ragnarök is an important event in Norse mythology and has been the subject of scholarly discourse and theory throughout the history of Germanic studies.
In the Poetic Edda poem Völuspá, references to Ragnarök begin from stanza 40 until 58, with the rest of the poem describing the aftermath. In the poem, a völva (a female seer) recites information to Odin.
The völva then describes three roosters crowing: In stanza 42, the jötunn herdsman Eggthér sits on a mound and cheerfully plays his harp while the crimson rooster Fjalar (Old Norse "hider, deceiver") crows in the forest Gálgviðr. The golden rooster Gullinkambi crows to the Æsir in Valhalla, and the third, unnamed soot-red rooster crows in the halls of the underworld location of Hel in stanza 43.
Ragnarök was first prophesised by the Jötunn Seeress Gróa, who unintentionally saw a vision of the actual events while searching in her library for ancient tomes for knowledge that would help her find her lost husband Aurvandil. In her vision she saw the beginning of Fimbulwinter, Skol and Hati devouring the Sun and Moon, Sutr emerging from Muspelheim, Fenrir breaking free from his chain and the Gods once again at each others throats. She also saw a white ghost from another land and his young son, Kratos and Atreus, who are at the center of everything. However, her vision was so powerful that it was felt by Odin himself, who promptly journeyed to Gróa's library to demand what she had seen. Seeing the Seeress was hesitant to tell him anything, Odin strangled her to death taking her knowledge in the process, but not before coldly revealing that Thor had killed her husband long ago.
However, Gróa managed to have the last laugh as Odin was seemingly not able to take all of her knowledge regarding the events of Ragnarök and only learned some of the main figures to be involved. He continued to try and gather more knowledge surrounding the events. Knowing that the rest of Jötnar also possessed the gift of foresight as well, he manipulated his son Tyr into arranging a meeting with the Giants in their home-realm of Jötunheim in order to try and steal some of their secret knowledge on the events of Ragnarök. Under the guise of brokering peace between the two races, Odin managed to gain entrance to the realm of the Giants and proceeded with Tyr to the meeting hall. Distracting the Jötnar with the false promise of handing over Mjölnir to them for the sake of peace, Odin managed to catch a glimpse of a hidden tapestry that depicted Kratos and Atreus in the events of Ragnarök, but he did not know who they were. However, his treachery was quickly discovered and the Giants forever banished him from Jötunheim before he could learn anymore.
As a result, Odin and by extension the rest of the Aesir, did not have a clear picture of Ragnarök and could only piece together the parts he managed to gather so far, which resulted in the Aesir misunderstanding certain events and when exactly they were supposed to happen, such as Baldur's death.
However, the Giants foresaw everything that was meant to happen in Ragnarök and carved out the events leading up to it as a mural one of their walls in Jotunheim.
- Baldur's death is the first mark of the coming of Ragnarök.
- The "Fimbulwinter", a three-year-long winter following Baldur's death. Its end is the second mark of Ragnarök.
- Sköll and Hati will devour the Sun and the Moon, marking the start of Ragnarök.
- Surtr, the first Fire Giant, will burn Asgard to the ground using his flaming sword, but is killed by Thor and Odin. However, the grand cycle of death and rebirth continues and Surtr is hiding in Muspelheim, awaiting for the day Ragnarök begins.
- The war between the Aesir and Vanir is continued.
- Fenrir will battle Odin, during which they are both killed.
- A fierce battle between Jörmungandr and Thor will happen, where the Thunder God strikes the World Serpent so hard that Yggdrasil splinters and sends the Serpent back in time.
- Kratos and his son Atreus intervene, only for Kratos to apparently die.
- At some unknown point, Atreus meets up with a pair of wolves and the three of them travel together.
- Despite the fact that Mimir was an ally of the Giants, it appears that they decided to not tell him of the full events of Ragnarök, which resulted in him only being able to assume what the events were with the disconnected knowledge that the Aesir themselves had. This led to him incorrectly stating that the prophecy did not take into account the presence of Kratos and Atreus, when in fact they were involved from the very beginning.