While members of the Celestial Bloodline have their powers originate from angelic influence in their family history, the Infernal/Abyssal Bloodlines can boast with fiendish heritage. These sorcerers have their power come from corruption and evil, whether this comes from one of the Nine Hells, or the Countless Layers of Abyss, it doesn't matter, they are shunned and feared throughout the world.
At 1st level, you choose one type of fiend as your ancestor. This will affect your features you gain later, as well as the source of your powers.
Devil - Infernal
Demon - Abyssal
You can speak, read and write either Infernal or Abyssal. Additionally whenever you make a charisma check when interacting with fiends, your proficiency bonus is doubled if it applies to the check
Your fiendish blood makes you more resilient. Starting at 1st level you gain resistance to poison damage and advantage on your constitution saving throws
Starting at 6th level, as a bonus acion you can spend a sorcery point to enhance your weapons with a sickening, supernatural poison. For every sorcery point spent, you can add 1d6 poison damage to the next successful strikes. The poison lasts for rounds equal to your Charisma modifier.
At 14th level, you gain the ability to sprout a pair of leathery wings
from your back, gaining a flying speed equal to your current speed. You
can create these wings as a bonus action on your turn. They last until
you dismiss them as a bonus action on your turn.
You can't manifest your wings while weaing armor unless the armor is
made to accommodate them, and clothing not made to accommodate your
wings might be destroyed when you manifest them.
Beginning at 18th level your fiendish powers reach their maximum potential. By sacrificing your own health, you can empower the spells. When casting a spell that deals damage, you can suffer a level of exhaustion to reroll any number of damage dice. You can only use this feature once per spell, and you must take the second roll.