Your Dexterity score increases by 2, and your Wisdom score increases by 1.

Young dragonborn grow quickly. They walk hours after hatching, attain the size and development of a 10-year-old human child by the age of 3, and reach adulthood by 15. They live to be around 80.

Although good in alignment, they are very whimsical, making and changing decisions frequently.

Mercury Dragonborn's are smaller, more nimble and almost looks sickly compared to other Dragonborns, being just under 6 feet tall and averaging almost 200 pounds. Your size is Medium.

Your base walking speed is 35 feet.

Mercury Dragon scales are like mirrors catching and reflecting light. Being a Mercury Dragonborn your scales have the same quality catching and reflecting light. When you reach 3rd level, you can cast the Mirror Image spell as a 2nd-level spell once with this trait and regain the ability to do so when you finish a long rest. Also when a creatures within 5 feet of you, unless in total darkness, they have disadvantage to hit you.

Seeing as your scales are mirrors, on your turn you can use a bonus action to redirect light, as low as dim light, to impose disadvantage to attacks for 1 round to a creature up to 30 ft to you, as long as they don't have full cover or are blind. 

You can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

Seeing as most of your scales are mirrors, unless your in total darkness you have disadvantage to stealth.

The Dragonborn fires a beam of brilliant, yellow light. The beam is 5 feet wide and extends 30 feet from the creature’s mouth. Any creature caught in the beam receives damage from heat. The DC for this saving throw equals 8 + your Constitution modifier + your proficiency bonus. A creature takes 1d10 fire damage on a failed save, and half as much damage on a successful one. The damage increases to 2d10 at 6th level, 3d10 at 11th level, and 4d10 at 16th level.

You can use your Breath Weapon a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

You have resistance to fire damage and are immune to being blinded

You can speak, read, and write Common and Draconic. Draconic is thought to be one of the oldest languages and is often used in the study of magic. The language sounds harsh to most other creatures and includes numerous hard consonants and sibilants.