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Bloodmages are practitioners of bloodmagic. The shadowbinders and bloodmages of the Further East are said to work their terrible sorceries at night. They are welcome in Asshai, where they can practice their arts and rituals with impunity.
Bloodmages were prominent in the Valyrian Freehold. Septon Barth, in his Dragons, Wyrms, and Wyverns: Their Unnatural History, speculated that the bloodmages of Valyria employed wyvern stock to create dragons. In the flesh pits of Gogossos, bloodmages mated beast to slave-women to bring forth twisted half-human children. Magic is said to have died out in the west after the Doom of Valyria, however.