Blodeuwedd

In the Fourth Branch of the Mabinogi, Blodeuwedd is created by Math fab Mathonwy and Gwydion as a magical solution to a tynged placed on Lleu Llaw Gyffes by Arianrhod that he should not have a human wife. The magicians gather specified flowers—commonly listed in the narrative as flowers of the broom, meadowsweet and oak—and from these conjure and baptize "the fairest and most beautiful maiden anyone had ever seen," naming her Blodeuwedd (literally 'Flower-Faced' or 'Flower-Aspect'). She is thus an intentionally constructed human figure with legal and social roles enacted within the tale (wife, agent) but whose creation is explicitly magical.

As created, Blodeuwedd is described in the Mabinogi as an exceptionally fair human maiden, formed from flowers (broom, meadowsweet, oak) and given a name and a place in society through baptism. After her betrayal, Gwydion transforms her into an owl (Welsh tylluan/gwdihŵ); the tale records that she shall not show her face by day and will be harassed and despised by other birds, associating her transformed appearance with nocturnality and the physical and behavioral traits of an owl.

Within the story Blodeuwedd displays human-level agency and cunning: she takes a lover (Gronw Pebr), solicits from Lleu the precise conditions of his vulnerability, and arranges an attack that nearly kills him. She is a magical construct rather than an independently documented practitioner of magic: the narrative shows her as created by, and later subject to, the arts of Math and Gwydion. The tale attributes restorative and coercive magic (englynion sung by Gwydion to restore Lleu; Gwydion's transformation of Blodeuwedd into an owl) to those magicians rather than to Blodeuwedd herself.