Ymir is attested in the Poetic Edda, compiled in the 13th century from earlier traditional material, in the Prose Edda, written by Snorri Sturluson in the 13th century, and in the poetry of skalds.
, is a monstrous wolf in Norse mythology. Fenrir, together with Hel and the World Serpent, is a child of Loki and giantess Angrboða.
due to the gods' knowledge of prophecies foretelling great trouble from Fenrir and his rapid growth, the gods bound him and as a result Fenrir bit off the right hand of the god Týr
Surtr is foretold as being a major figure during the events of Ragnarök; carrying his bright sword, he will go to battle against the Æsir, he will do battle with the major god Freyr, and afterward the flames that he brings forth will engulf the Earth.