Dodon Ray

You fire a superheated beam from your finger in a 5-foot-wide, 60-foot-long line. Creatures struck by the beam must make a Dexterity saving throw. On a failed save the creature takes 3d10 radiant damage and has its speed halved until the start of your next turn. On a successful save the creature takes half damage and its movement is unaffected.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d10 for each slot level above 2nd.