The mythological creatures that could transform themselves into ravens, swans, and wolves were valkyries celtic warrior-goddesses amazons none of these; mythological creatures could only take one form

The Valkyries were the mythological creatures that could transform themselves into ravens, swans, and wolves. A valkyrja is a term used to describe an often beautiful female figure that is also a soldier of battle, sometimes described as having wings themselves or getting about by riding a magnificent winged horse. They are portrayed carrying various weapons, almost always accompanied by a shield, sword and or spear. 

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