Who is Efnisien from The Mabinogion and what is their importance? Mabinogion English & Literature Efnisien | The Mabinogion

Efnisien appears in the story, Branwen Daughter of Llyr. He loves battle and strife, and it is Efnisien's mutilation of the the Irish horses that causes the war between Bran and Mathowlch. Although, he is sometimes helpful, Efnisien often causes needless harm and violence. He personifes the forces of death and chaos.