EDIT: I knew that I had seen this somewhere in the forums: https://en-forum.guildwars2.com/discussion/comment/969914/#Comment_969914 Mike-OBrien-ArenaNetArmor sets are by far the most expensive reward we can make. A full set includes heavy, medium, light, times five races, times two sexes, so it's like developing 30 sets. It takes nine months to develop. (That's for a normal armor set -- legendary is much longer.) It's not something we can do for Living World episodes. Individual pieces are good rewards for Living World episodes; full sets are more something for expansion packs.