Warp Gambit

When you are targeted for an attack, you can start casting Warp Gambit, by doing so your form starts to shift and blink. This provides a +2 bonus to AC. 

Casting the spell leaves you vulnerable, as such if the attack made against you is successful, it counts as a critical hit and the spell ends, if the attack made is unsuccessful you teleport up to 15 ft (this does not provoke attacks of opportunity)and the spell ends.

The AC bonus increases by 1 every five levels.