Bone Armor

This spell rips the bones from the caster's enemies to form a suit of very tough armor around said caster. Choose up to 2 creatures within range. Your spell rips the bones from their bodies, dealing 1d8 piercing damage to each of them, and forming a suit of armor around you out of those bones, increasing your AC by 1 per target for the duration of the spell or until concentration is dropped. You can only have a maximum of +4 AC at a time from this ability. This ability replaces all bonuses to AC gained from dexterity bonuses for the duration or until concentration is dropped. Targets stack AC between consecutive castings up to the maximum.