An ritual raven knife is used to commit murder in the episode "Blackwing". It is one of a pair of such knives, each carved from the same piece of obsidian. They belonged to Gary Blackwing. Blackwing has the only surviving copy of a treaty made between the British government and the Mississauga Indians in the eighteenth century. He is murdered so that he will be unable to produce it as evidence in a land claim that is about to go to court. The knife is carved out of obsidian. The hilt of the knife is shaped like the head of a raven.