Breath of the Dragon

You can use your bonus action to exhale destructive energy. Your breath weapon deals fire damage. When you use your breath weapon, each creature in the area of the exhalation must make a dexterity saving throw. The DC for this saving throw equals 8 + your Constitution modifier + your proficiency bonus. A creature takes 3d6 damage on a failed save, and half as much damage on a successful one. The damage increases to 4d6 at 6th level, 5d6 at 11th level, and 6d6 at 16th level. After you use your breath weapon, you can’t use it again until you complete a short or long rest.