Ill-Fated Word

1st-level divination (chaos)
Casting time:
Range: 1 reaction, which you take when an enemy makes an attack roll, ability check, or saving throw
Target:
Components: V
Duration: Instantaneous
Classes: Bard, Sorcerer, Wizard
Subclasses:

You call out a distracting epithet to a creature, worsening its chance to succeed at whatever it’s doing. Roll a d4 and subtract the number rolled from an attack roll, ability check, or saving throw that the target has just made; the target uses the lowered result to determine the outcome of its roll.