Fewash Welko was a Selkath member of the Order of Shasa. He was one of the Shasan adepts who, shortly before the Battle of Endor, met a dark-suited Human Jedi and was convinced to rise up against the Imperial forces occupying Ahto City. Welko was one of the two hundred Shasans who engaged in the dark side-fueled massacre, and afterward was informed by the "Jedi" that they now served the same master.
He eventually wrote the book, The Battle of Ahto: A Memoir.
Sources
Manaan: Depths of History: Part 4: Blades of Rebellion on Wizards.com (original site is defunct) (First mentioned)
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