Heroic Endorian Guard
During a visit to Frosta's Kingdom of Snows, Adora & Glimmer were captured by Endor's guards & taken to his castle. They escaped but She-Ra went back & learned that Etheria's greatest wizard Endor had stopped time in his castle but returned to normal time to steal magic to keep his wife alive & maintain his time spell.
After She-Ra cured King Endor's wife from her slumber, King Endor left one of his guards behind to join the Great Rebellion when his castle teleported to the Land of Legends.
Ptarmigan, like all Endorian Guards, can transform into a white bird. When he isn't fighting the Horde he lives in the Kingdom of Snows.