At Caer Dallben, after Arawn Death-Lord stole the enchanted sword Dyrnwyn from Prince Gwydion, the enchanter Dallben consulted the oracular pig Hen Wen to determine how the sword might be regained. At first Hen was too terrified to acquiesce. Yet while the Companions watched, Taran Assistant Pig Keeper calmed her, and gently persuaded her to use her powers of prophecy for the good of all Prydain.
During the reading, the ash rods -- called Letter Sticks -- which Dallben used to receive Hen's messages shattered. Thus Hen Wen's prophecy remained unfinished. The oracular pronouncement proved to be vague yet dire, hinting at dark fate and impossible events:
"Ask, sooner, mute stone to speak and voiceless rock to speak. Quenched will be Dyrnwyn's flame; Vanished, its power. Night turn to noon And rivers burn with frozen fire Ere Dyrnwyn be regained."
Below you'll find how each line of Hen Wen's prophecy came true. The events are listed in the order they occur in the prophecy itself, rather than in chronological order as they occurred in the story.
Mute Stone, Voiceless RockMount Dragon, three Cauldron-Born warriors beset Taran, he sought a weapon and heard the wind keening through holes in a large stone. He wrenched the boulder free, toppling two of the warriors; in a hollow he found the sword Dyrnwyn, seized the blade and with it pierced the breast of the Cauldron warrior, killing it instantly and causing all the other Cauldron-Born to die with a final shriek.
Quenched and Vanished
Chapters XIX and XXI
Night to Noon
In the Hills of Bran-Galedd, Eilonwy spotted a long column of Huntsmen of Annuvin -- hundreds of them -- marching straight toward the entrance to the Fair Folk mines, from which Taran's band suddenly emerged. Realizing the two were unaware of each other and that the Commot men would be trapped against the rocks and slaughtered, Eilonwy lifted her bauble high and lit it more brightly than ever before -- so bright it seemed "the sun itself were bursting from the mountainside.... The whole valley had turned bright as noon."