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

Your Charisma score increases by 2. An additional ability score based on your subrace increases by 1.

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.

When a creature you can see deals damage to you, you can use your reaction to call doom upon it, causing it to take necrotic damage equal to 1d10 plus your level. Once you use this trait, you can’t use it again until you finish a long rest.

You know the thaumaturgy cantrip. Your spellcasting ability for this spell is your choice of Itelligence, Wisdom, or Charisma.

Your spellcasting modifier is your choice of Intelligence, Wisdom, or Charisma. Your spell save DC and spell attack modifier are listed below. You use the same modifier for any save DCs from your race, such as the subrace transformation features.

You choose one of the following subraces, which determine your ASIs (factored into the Ability Score Increase feature) as well as granting additional features.