Impact Cloak

Requires attunement. This normally flexible and stylish hooded cloak magically hardens to intercept incoming attacks. The cloak has 20 charges. When you are
targeted by an attack, it sets your base AC from
11 + dex to as much as 15 + dex. More charges are
spent the higher the AC; 1 charge for each number
above 10. The cloak only spends charges when it needs
to, and only the amount needed to avoid you being hit.
If it cannot increase your base AC high enough to
avoid being hit, it spends