Kayso was a pirate and leader of the Black Hole Gang. He was not a very capable leader, and kept much of the group's spoils to himself. When this was discovered, he was killed by Amaiza Foxtrain, who took his place as leader.
Sources
"The Starhoppers of Aduba-3" — Star Wars Gamer 4 (First mentioned)
Amaiza in the Databank (original site is defunct)- So Uncivilized: Great Gunslingers in Star Wars Part 1 on StarWars.com (original link is obsolete)
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