You have resistance to fire damage.

You know the thaumaturgy cantrip. When you reach 3rd level, you can cast the hellish rebuke spell as a 2nd-level spell once with this trait and regain the ability to do so when you finish a long rest. When you reach 5th level, you can cast the darkness spell once with this trait and regain the ability to do so when you finish a long rest. Charisma is your spellcasting ability for these spells.

Your Dexterity score increases by 2.

Although elf/tieflings reach physical maturity at about the same age as humans, the elven understanding of adulthood goes beyond physical growth to encompass worldly experience. An elf/tiefling typically claims adulthood around the age of 40 and can live to be 500 years old.

Elf/Tieflings range from under 5 to over 6 feet tall and have slender builds. Your size is Medium.

Your base walking speed is 30 feet.

Accustomed to twilit forests and the night sky, 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 proficiency in the Perception skill.

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