Lady Sariel is a powerful PC turned NPC spanning several campaigns.
Biography
In Matt's previous campaigns
Sariel became a fervent foe to Saint Ajax the Invincible when her father, the elven king of the Orchid Court, swore fealty to Ajax. During a battle with a scion of Orcus, she was killed and turned into a vampire spawn. When the Scion was killed, she regained her free will and became Lady Sariel the Vampire Queen. She began collecting the Teeth of the Dragon, believing that by collecting all of them, she could "raise the Dragon" and use its power to destroy Ajax. She is known to have collected three: Arcturus, Scorpius, and Orion. She also gained control of the Oracle.
The Siege of Castle Rend
Disguising herself as Sir John, a minstrel of the Baron of Tor, she secured an invitation into Castle Rend. Once inside, she revealed herself to Nekodemus and demanded that he hand over Arcturus and Scorpius so that she could raise the Dragon and destroy Ajax. Upon learning that Sariel had attained Orion, Nekodemus attempted to attack Sariel with his enchanted great axe Wound. The attack, which should have been devastating, was ineffectual as Wound refused to harm the wielder of the Master Sword. Sariel had one of her retainers, a death knight, bring in a captured Lord Saxton as a prisoner, offering him in exchange for the swords. As proof of her power, she summoned Balthair from the ground, now a vampire spawn under her control. The residents of Castle Rend finally accepted her bargain and handed Arcturus and Scorpius over to Lady Sariel.
The Final Contract
At the beginning of The Chain campaign, Lady Sariel, Baron Nekodemus of Bedegar, and Duke Kenway of Dalrath hire The Chain of Acheron to assassinate Ajax's Archwizard, Mortum.
In what appears to be her final confrontation with Ajax, Lady Sariel struck at him with the sword named Orion. Ajax countered her attack with the Jade Fist and in doing so destroyed Orion. The ensuing blast disintegrated Lady Sariel. Her current fate remains unknown.