Koth'Vaul emerged from the Abyss millennia ago. Disguised as wise advisors, he tempted numerous mortal rulers to damnation and disappeared before any of them could understand, earning respect among many lesser demons. He was eventually imprisoned underground after a cabal of Thassilonian wizards discovered his deception and exposed part of his true name. As time weakened his wards, Koth'Vaul tried to break through them but was banished by Pathfinder Society agents to the Abyss.1
Koth'Vaul quickly learnt about the events on Golarion since his imprisonment, gathered strength and researched the Pathfinder Society. He aided the corrupted Venture-Captain Thurl and aided his siege of Absalom,2 abandoning him when the siege failed. At the same time, the Mendevian Crusades ended in victory: the Worldwound was closed and the demon lord Deskari killed. Knowing that a fragment of Deskari's power still lurked in his corpse, Koth'Vaul travelled to the Rift of Repose and stole one of Deskari's hearts, to fuel his transformation into a demon lord himself, then hid in an unclaimed part of the Abyss which he could later claim as his own.1
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