Any conscious creature you touch hallucinates, seeing terrible visages from its worst nightmares, and is unable to tell dream from reality. 

The Creature must make a DC 15 Wisdom saving throw. On a successful save the creature takes 3d6 psychic damage and the spell ends. If the creature fails, it becomes frightened by you and the closest number of creatures to it, of which it is not already frightened, up to a number equal to your spellcasting ability modifier. For instance if your spellcasting ability modifier is '+3' the creature will become frightened of you and the 3 creatures it is closest to.

While the creature is frightened, it must make a wisdom saving throw on each of it's turns, for each successful wisdom saving throw it makes remove one creature from the total number of creatures of which it is frightened, leaving yourself until last (which creature it is no longer frightened by is up to the DM). If it fails this saving throw the total number of creatures remains unchanged.  If the creature successfully makes Wisdom saving throws for each creature and yourself the spell ends.  For instance if the creature is frightened by you and 3 other creatures and makes a successful saving throw on it's turn this number is reduced by 1, to you and 2 other creatures. If on it's next turn it fails to succeed on the saving throw this number would remain the same until it makes another successful save.