Darkbeam

A beam of inky darkness is emitted from your hand in a 5-foot-wide, 60-foot-long line. Each creature in the line must make a Constitution saving throw. On a failed save, a creature takes 3d8 cold damage and 3d8 necrotic damage and is blinded until your next turn. On a successful save, it takes half as much damage and isn't blinded by this spell. Add 1d8 cold damage and 1d8 necrotic damage per spell level when you cast this spell above 6th level. Celestials have disadvantage on this saving throw. 

You can create a new line of darkness as your action on any turn until the spell ends.

For the duration, darkness radiates from the palm of your hand in a 30 foot radius, dowgrading all light in that area. The effects of Sunlight in this area are blocked and it becomes dim light. Bright light in this area also becomes dim light, and dim light becomes full darkness. Darkness created in this manner is magical darkness.