Ragnarok

Ragnarok is the name given to a past event in which the Norse gods of both the Æsir and the Vanir are killed by Loki, Jörmungandr, and Fenrir, which causes the ascension of Víðarr to the position of the sole surviving Æsir and the prophesying of the Spáðinn, a mythical mortal figure who will, in turn, slay either Víðarr or the trio of Loki, Jörmungandr, and Fenrir and prevent a Second Ragnarok.