The Corvids, whether crows, ravens, or magpies, have all played significant roles in world folklore and myth. They are, by turns, bringers of wisdom, harbingers of both good and bad news, or tricksters who can aid a hero or unmask a villain. The rhyme at the beginning of this introduction is an Old English chant recited when seeing a flock of crows. The Norse god Odin had a raven as his companion, and the Haida of the American Pacific Northwest used ravens on their totem poles and created elaborate raven masks.