Dragonskin

You touch a willing creature. Until the spell ends, the target’s skin hardens and takes on the scale-like consistency and color of a specific dragon type, and the target’s AC can’t be less than 17 no matter what type of armor they are wearing. Additionally, the target gains resistance to one type of damage determined by the kind of dragon providing the scale as the material component of the spell, and the target gains advantage on saving throws against the breath weapon of dragons.