M'ridin first appears in The MasterHarper of Pern. He transports Merelan and Petiron to Nerat. After S'loner's death, M'ridin serves on the Council (with M'odon, C'rob, and C'vrel) that runs the Weyr until F'lar became Weyrleader. M'ridin, like many Dragonriders, believed in the return of Thread.