Atlas's Alliteration Affinity

You place a curse on a creature that you can see within range. Their tongue tickles tremendously. Until the Spell ends, whenever the cursed creature wishes to speak, they must succeed on an Intelligence Saving Throw against your Spell Save DC to come up with an alliteration. On a failed save, the creature is mute and cannot say anything.

Using a Higher-Level Spell Slot. You can target one additional creature for each spell slot level above 1.