True Color Spray

Unlike the mundane Color Spray practiced by hedge witches and student wizards, this spell includes the 8th color, the Color of Magic, elbowing its way amongst those ordinary colors.

You launch a dazzling array of flashing, colorful light including an insistent element of yellowish-green purple. Each creature in a 15-foot Cone originating from you must succeed on a Constitution saving throw or have the Blinded condition until the end of your next turn. Arcane casters and cats know at a glance what you did there.