After a bad throw with his throwing stone, Korg accidentally kills a woodpecker instead of his intended target. Seeing a bird flying above just then that is looking down on them, Korg feels it curses him. A string of unlucky events soon convinces him of the truth of this more than ever. So his family won't suffer his bad luck, Korg goes into a self-imposed exile. But his family misses him and works to retrieved Korg.
—Jilerb