You can breath both water and air.

You can breath a 5 by 20ft line of fire, the targets must take a 14 DEX save, on a failed save taking 1d8 fire damage, or half as much on a successful one.

You have set of scales that cover your skin, providing an AC of 10 +DEX Modifier.

Your Slick and Lean body structure allows you to make quick and agile movements. You have +2 Dexterity.

Thanks to your infernal heritage, you have superior vision in dark and dim conditions. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray.

You have immunity to fire damage.

You can speak, read, and write Common and Infernal.