Cloak of Night

You cloak yourself in shifting magical shadows.  While cloaked, you seem to phase in and out of existence, as the shadows cling to you.  Any creature trying to attack you must first succeed on a Wisdom (Perception) check against your spell save DC.  On a fail, all attacks made against you by this creature this turn automatically misses.  On a success, all  attacks made against you by this creature this turn are made at disadvantage.  While in dim light or darkness, you are invisible while motionless.