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

Elf-Tieflings reach adulthood around 20 and can live to be over 150.

Elf-Tieflings have conflicting alignments. They can share the chaotic tendencies of both races but can also lean more towards the evil side. 

Elf-Tieflings are generally around the height of a human ranging from 5 feet towards 6 feet. Your size is Medium.

Your base walking speed is 30 feet.

Thanks to your 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 advantage on saving throws against being charmed. However, due to the conflicts of heritage, magic can put you to sleep.

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.

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