Breath from the Depths

Once per short rest, you pull the ancient power of your ancestors from your depths and erupt a powerful spray of your Dragon Color Type damage type in a 30ft line, or a 15 foot cone. Target creatures makes a DEX Save equal to 10+ your CON modifier as the DC. On a failed save they take 3d6 damage, on a successful save they take half. 

This ability has a 5-6 recharge rate, though if you use this ability more than once per short rest, you take a point of exhaustion. 

At Levels 6, 11,  & 16 the damage dice increases by 1. So at 6th level it does 4d6, 11th level 5d6, 16th Level 6d6