Tummy Turmoil

You choose a creature within your sight and speak the words "tummy turmoil." The affected creature has instant, aggressive diarrhea. They do not take physical damage from this, but 4d8 psychic damage from the horrific experience they have just endured. 

At Higher Levels. When you cast this spell using a spell slot of 5th or higher, the damage increases by 1d8 for each slot level above 4th.