Greywood

This elegant garment is made from exquisite cloth of white, gray, or black and adorned with silvery runes. You can't attune to a robe of the archmagi that doesn't correspond to your alignment. You gain these benefits while wearing the robe: If you aren't wearing armor, your base Armor Class is 15 + your Dexterity modifier. You have advantage on saving throws against spells and other magical effects. Your spell save DC and spell attack bonus each increase by 2.