Armor of Shadows

You touch a willing creature who isn't wearing armor and channel magic from the Shadow Weave. The shadows within the area surrounding the target coalesce into a set of shifting jet-black interlocking plates from the waist up, spiked jet-black pauldrons, and a fine black robe filled with spiraling, trapped shadows gifted from Shadow Weave. The helm is constituted of two black spiraling horns with a facemask that shows the horrifying visage of a tortured soul, crafted by solidified shadows. 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. The spell stays in effect for the full duration.