Blue Death (5e Spell)
From D&D Wiki
|Casting time:||1 action|
You surround a creature in illusion magic to make them believe that they are in a life-threatening scenario. A creature you see within range must succeed a Intelligence saving throw or take 1d6 psychic damage. In addition, they have disadvantage on the next Intelligence saving throw they make before the end of its next turn.
At Higher Levels. The spell's damage increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).