You conjure a spectral battalion of soldiers wielding spears and shields made of light. The soldiers fill a 20-foot cube centered on a point you can see within range. The cube is filled with bright light, and you and friendly creatures within the cube have half cover. The cube is difficult terrain for hostile creatures. As a bonus action on your turn, you can move the cube up to 20 feet. A hostile creature that enters the cube for the first time on a turn or starts its turn there must make a Dexterity saving throw, taking 2d8 piercing damage and 2d8 radiant damage on a failed save, or half as much damage on a successful one.