Wild King MacPhearsome was the huge and powerful eagle king of the northern mountains. Despite his unpredictable personality and status as a bird of prey, he proved to be a goodbeast; he was very impressed by the courage and determination of Thrugg the otter and his traveling companion Baby Dumble the dormouse Dibbun. As a result, he allowed them to pick from his mountain the Flowers of Icetor, the cure for the Dryditch Fever epidemic that had broken out at Redwall Abbey. He even went so far as to carry Thrugg's haversack, with Dumble and the flowers aboard, back to the Abbey. Dumble never forgot the experience; even as an old dormouse, he still waited out on the Abbey Grounds for MacPhearsome to someday come back. MacPhearsome spoke with a broad Highland accent, like most Northern Birds of Prey.
Argulor and MacPhearsome are the only eagles in the series.
His name is a play on the common Scotch surname "Macpherson" and the word "Fearsome".