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Ser Alastor Reyne was a knight from House Reyne during the early reign of King Jaehaerys I Targaryen and the master-at-arms at Casterly Rock.
During the early reign of King Jaehaerys I Targaryen, Ser Alastor was the champion of the westerlands and the master-at-arms at Casterly Rock, in the service of Lord Lyman Lannister.
Ser Alastor was one of the notables that participated in the grand melee in the Dragonpit in the tourney for its completion in 55 AC.