Celeste’s Aurora Mantle

You touch a willing creature who isn't wearing armor, and a shiny protective magical force surrounds it until the spell ends. The target's base AC becomes 13 + its Intelligence modifier. The spell ends if the target dons armor or if you dismiss the spell as an action.

Also, as long as the creature is wearing this Aurora Mantle, they will gain Psychic and Necrotic damage resistance but Radiant damage vulnerability. Also, if you receive Radiant damage, make a DC10 Constitution saving throw, on a failed save, you are blinded for 1 round.