Blood Armor

Blood forms into a protective layer around you until the spell ends.  For the duration of the spell, your base AC becomes 16 (which cannot be improved by armor or dexterity).  The spell ends if you dismiss the spell as an action.  

At higher levels - When you cast this spell using a spell slot of 3rd level, the bas AC increases by +1 for every two slot levels above 2nd.  The spell component of the spell increases as well when casted at higher level, becoming base of 5 HP + spell level (example - 4th level the AC is set at 17, but the blood component is 9 HP)