Torrent of Darkness

You summon a torrent of darkness to flood your enemies. Summon a 50 ft. wide torrent of darkness in front of you that floods forwards like water for 120 ft. Any creature hit by this spell takes 5d8 necrotic damage and must make a Constitution saving throw every time their turn passes: on a failed save they are blind until they make their next save attempt, and on a successful save target only takes damage and isn't blinded.