Gildas was an enchanter who lived during the reign of Queen Regat Daughter of Llyr, a generation before the time of Taran and Eilonwy.
Bald wizard
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The Foundling and Other Tales

In this book of short stories, in the third tale titled "The True Enchanter", Gildas is described as the first suitor who came seeking the hand of Princess Angharad in marriage. He was "paunchy, with fleshy cheeks shining as if buttered", and splendidly attired in gold and jewels. Yet his demeanor was officious and purely concerned with business, and when called upon by the Princess to demonstrate his enchantments, he could summon only darkness. When Angharad called into question the practicality of such a spell -- given that all one had to do was wait for night to fall -- Gildas offered to summon a blizzard or a feast, but failed to persuade the Princess that his magicks were in any way useful.

Magical Forest
Later, after Angharad had fled the court with her chosen suitor Geraint, Queen Regat dispatched Gildas and another wizard, Grimgower, to pursue the eloped lovers. In the forest beyond the Castle of Llyr, Gildas sought to blind the pair by casting his trademark spell of inky darkness, but the Princess only drew out her bauble -- the Golden Pelydryn which would shine only for the compassionate and the caring -- and so banished the blackness.
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