Babble

This spell causes the speech of affected creatures to sound like nonsense. A creature you can see within range must succeed on an Intelligence saving throw when you cast this spell or be affected by it. An affected creature cannot communicate in any spoken language that it knows, nor can it understand any spoken language. When it speaks, the words come out as gibberish. Spells with verbal components cannot be cast. The spell does not affect telepathic communication, nonverbal communication, or sounds emitted by any creature that does not have a spoken language. As an action, a creature under the effect of this spell can attempt another Intelligence saving throw against the effect. On a successful save, the spell ends.