Lluagor was a horse, a bay mare who was originally Adaon's steed.
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After Adaon died, Lluagor was given to Taran along with the Son of Taliesin's other possessions. Taran first bade Gurgi and Fflewddur to ride Lluagor, but the mare soon became Eilonwy's favorite, and the Princess often rode her thereafter.
With Taran's stallion Melynlas, Lluagor had a foal named Llamrei.