The Archive of Esoteric Secrets
7-level Illusion
Each creature that you choose within range must succeed on a
Wisdom saving throw. On a failed save, it perceives all bright
light as dim-light, and all dim-light as darkness for the duration.
Any creature that starts its turn in an area it perceives as
darkness takes 3d6 psychic damage.
Darkness perceived by this spell counts as magical for the
purposes of overcoming creature’s with darkvision.