Dragon of Annwn
“a mottled, ridged, serpent
with a hundred souls, by their sin
tortured in the folds of its flesh”
-Cad Goddeu: The Battle of the Trees
Unagilis has woven magic into and through the Hill and the dragon to draw upon its power and/or contain its power. Lady Catherine claims that it guards the Gate to Arcadia. Nathaniel Widdershins has seen its immensity in a vision.
The consequences of tampering with the Dragon of Annwn are unknown.