Mass Faerie Fire

You can place up to three 20-foot cubes each centered on a point you can see within range. Each object in a cube is outlined in blue, green, or violet light (your choice). Any creature in a cube when the spell is cast is also outlined in light if it fails a Dexterity saving throw. A creature in the area of more than one cube is affected only once. Each affected object and creature sheds dim light in a 10-foot radius for the duration.
Any attack roll against an affected object or creature has advantage if the attacker can see it, and the affected creature or object can't benefit from being invisible.