Disturbed sleep

The target makes a Charisma saving throw. If the target succeeds then nothing happens. On the other hand, if the target fails its roll then the spell plunges the target into a dream or a nightmare of the caster's choice : 

-If it's a dream, then the target is incapacitated until hit with an attack. 

-If the caster chooses the spell to be a nightmare, then the target sees everyone around as an enemy trying to harm it and goes after the nearest creature.

The spell doesn't work on creatures such as elf that can't be put to sleep.