Orddu, Orwen and Orgoch

Orddu, Orwen, and Orgoch are fictional characters in Lloyd Alexander's Chronicles of Prydain series.

They are three witches who live alone in the Marshes of Morva. Although their identities are apparently fluid and interchangeable, each persona has a distinctive appearance: Orwen wears a necklace of milky stones, Orddu's hair is adorned with many ornaments, and Orgoch's face is shadowed by a black cowl. They were the original owners of the Black Cauldron and lent it to Arawn, who used it to create zombie-like warriors, the Cauldron-Born. Later, they reclaimed it but were willing to relinquish it again in exchange for a magical price.

The Three Sisters, as they are known, are very mysterious beings, as one of the Fair Folk says to Taran, "It's more a question of what they are, not who they are." In one part of The Black Cauldron they turn from ugly, ancient hags and into three beautiful young maidens (from day to night). Orddu, Orwen, and Orgoch can also turn into each other, swapping their identities between them. They appear to take delight in tormenting intruders to their lair with talk of turning them into frogs and stepping on them, smiling the whole time as though they talk about jovial things. It appears that Orddu is the leader of the three, Orwen is the most cheerful and Orgoch seems to be the most disagreeable as neither of the other two sisters want to "be" her, and people seem most perplexed whenever she agrees to do something without grumbling. She also has a strong love for food and would devour anything on legs.

Despite their strange demeanor, the witches claim to not be evil (instead, being interested in things as they are) and indeed seem to seldom carry out their transformation threats, at least to Taran and his friends. They show a dislike of the Cauldron-Born, claim that Arawn spoiled their Cauldron for any of its other purposes, and seem pleased when Taran tricked several Huntsmen into sinking into a bog (it was also implied that they transformed several previous Huntsmen into animals). They also seem to consider stealing the Cauldron back from Annuvin no trouble.

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