Visions of Hadar

You choose up to three willing creature you can see within range and imbue them with terrible knowledge and visions of the future. For the duration, whenever one of these creatures makes an ability check, attack roll or saving throw, they may choose to take 1d4 psychic damage. If they do, they add 1d6 to that roll. The creatures can wait until after they roll the d20 before deciding to do this, but must decide before the DM says whether the roll succeeds or fails.