This armor combines plates of ashresin and fine mithril mail. It is also enchanted with powerful abjuring wards that provide protection against swords and spells alike. It is a favored type of armor among wizards who need to go into battle, or conduct potentially explosive experiments. While you are attuned to this armor, you are considered trained with it.
While you wear it, you have a +1 bonus to your AC, and you have advantage on saving throws against spells. Additionally, when you finish a long or short rest, you can choose any damage type except bludgeoning, piercing, or slashing and gain resistance to it until you select another damage type.