Kobold Viper

ability score increase: Choose one of: (a) Choose any +2; choose any other +1 (b) Choose three different +1

age: Kobold vipers reach adulthood at age 6 and can live up to 120 years.

Size: Small

speed: 30 ft.

Languages: You can speak, read, and write Common and Draconic, or one other language that you and your DM agree is appropriate for your character.

race features:
Darkvision. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were in dim light. You discern colors in that darkness only as shades of gray. Lightning Resistance. You have resistance to lightning damage. Kobold Viper Legacy. Kobold's connections to behirs can manifest in unpredictable ways in an individual kobold. Choose one of the following legacy options for your kobold.

Behir Bloodline. You have a climbing speed equal to your walking speed.
Craftiness. You have proficiency in one of the following skills of your choice: Arcana, Investigation, Medicine, Sleight of Hand, or Survival.
Defiance. You have advantage on saving throws to avoid or end the frightened condition on yourself.

Kobold vipers are kobolds who have forsaken their draconic heritage and thrown their lot in with an ancient enemy of dragons, the behir. Or the descendant of an individual who made such a decision.