BLADE BARRIER - Evocation - 6th Level

Casting Time: 1 Action
Range: 90 Feet
Components: V, S
Duration: Concentration, up to 10 minutes

You create a vertical wall of whirling, razor-sharp blades made of magical energy.  The wall appears within range and lasts for the duration.  You can make a straight wall up to 100 feet long, 20 feet high, and 5 feet thick, or a ringed wall up to 60 feet in diameter, 20 feet high, and 5 feet thick.  The wall provides three-quarters cover to creatures behind it, and its space is difficult terrain.
  When a creature enters the wall's area for the first time on a turn or starts its turn there, the creature must make a Dexterity saving throw.  On a failed save, the creature takes 6d10 slashing damage.  On a successful save, the creature takes half as much damage.

Source: 5th Edition SRD, Player's Handbook
Class List: Cleric.