The Three Harmful Blows of the Island of Britain:
Of the first, this is recounted in
The Mabiogion section called "
Branwen uerch Llyr"; it is because of this, that the battle of Ireland was fought, killing
Bran.
Of the second, this is a tradition I've only ever seen in the triads, that the Battle of Camlan was related to a fight between Guenevere and another woman, and not related to Mordred. Curious...
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