Introduction
Vali is a son of Odin, conceived specifically with the giantess Rindr in fulfilment of a prophecy that he would avenge Baldr's death. He is remembered for the speed and single-mindedness of his purpose: born and grown within a single day, he wastes no time before killing Hodr.
Note: this Vali should not be confused with Loki's son of the same name, mentioned in some sources among those punished after Baldr's death; the two figures are generally kept distinct.
Family
Rapid growth and vengeance
Unlike other gods, whose birth and maturation follow no special account, Vali's story emphasises his extraordinary speed: born for a single purpose, he grew to full adult size and strength within a day of his birth, refusing to wash his hands or comb his hair before completing his task, and killed Hodr without delay to avenge Baldr.
Survivor of Ragnarok
Vali is one of the gods prophesied to survive Ragnarok, alongside his brother Vidar, and to help populate and rule the renewed world afterward, according to the Poetic Edda's Voluspa.