Animate a pile of bones into a swirling barrier of bone surrounding you. The barrier has 50 hit points and takes damage equal to the hit when you save against an attack. While the barrier holds, you have a +2 bonus to AC.
If you use an animated skeleton under your command as material component for this spell, in addition to the effect above, if you save against a melee attack, your barrier lashes out making a Shortsword attack(as stated on the Skeleton creature entry) against the enemy follow all rules of the attack. If the barrier created this way lasts the entire duration it will reform into a skeleton under your command once the spelle ends.
At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the barrier hit points increase by 15 for each slot, and bonus to AC by +1 for every three slots above 3rd.