The Ichor of Vercingetorix

From the introduction:

The sages say that ages ago a Demon Lord by the name of Vercingetorix waged war across the realm, bringing all of mankind to its knees before his devastating horde. As Vercingetorix celebrated his victory in the Abyss, the kings of earth offered him sacrifices and gifts of homage, but Yeenoghu, his little brother, saw a chance for glory, attacking him during his revelry. The power of Vercingetorix’s essence was too powerful to be destroyed, but Yeenoghu was able to separate his immortal pieces. The pieces were then scattered by Yeenoghu’s cultists. Nearly three ages later a rogue Cleric of Yeenoghu, Mefyu, stumbles upon an urn filled with Vercingetorix’s ichor...