Dragon Blood

Dragon Blood (DB) is a reagent that is in use on Pagan, harvested from -as the name already says- dragons. However, its properties -specifically that of ice dragons- are also known on the Serpent Isle.

Serpent Isle
On the Serpent Isle, the Gwani of the Northern Regions had knowledge of the blood of the rare ice dragons having strong healing powers. However, as a dragon would hardly part with its blood peacefully, this became a major problem when they needed it to heal their young Neyobi. It was the Avatar who finally managed to get the needed blood.

Pagan
On Pagan, Dragon Blood was used in the magic scool of Thaumaturgy for the magical effect of adding serious power to a spell. Interestingly enough, despite Mythran selling the reagent, no live dragons were ever seen in the entirety of the Avatar's stay in the world. However statues of dragons were found in Tenebrae, hinting that the species is not unknown to the inhabitants of Pagan.

Ultima Online
When the Stygian Abyss expansion opened, it was found that the gargoyle Mysticism school of magic makes use of Dragon Blood as a reagent.