Fiendish Soul

The fiend-blooded, who have fiendish blood in them that corrupts their being, bring aspects of their fiendish forebear to the surface as they grow in power. This sinister heritage gives them strength in specific areas and lends their spellcasting a decidedly fiendish edge and more often than not people loose themselves to the evil nature within, but a rare few are able to master it and use the powers of the sinister forces of the multiverse for the purposes of good.

Fiendish Spells

1st-level Fiendish Soul feature

You learn additional spells when you reach certain levels in this class, as shown on the Fiendish Spells table. Each of these spells counts as a sorcerer spell for you, but it doesn’t count against the number of sorcerer spells you know.

Whenever you gain a sorcerer level, you can replace one spell you gained from this feature with another spell of the same level. The new spell must be a necromancy, enchantment, illusion, or fire damage dealing spell from the sorcerer, warlock, or wizard spell list. 

Fiendish Spells

Fiendish Heritage

1st-level Fiendish Soul feature

Your Fiendish blood gives you resistance to poison damage.

Fiendish Resilience

1st-level Fiendish Soul feature

As magic flows through your body, it causes physical traits of fiendish ancestors to emerge. Your hit point maximum increases by 1 and increases by 1 again whenever you gain a level in this class.

Additionally, your skin becomes otherworldly strong compared to a normal prime material plane native. When you aren’t wearing armor, your AC equals 13 + your Dexterity modifier.

Blood of Fiends

6th-level Fiendish Soul feature

Your fiendish essence grants you resistance to cold and fire damage or acid and lightning damage, your choice.

Demon Blood

You have resistance to acid and lightning damage.

Devil blood

You have resistance to cold and fire damage.

Fiendish Surge

14th-level Fiendish Soul feature

You can unleash the fiendish power surging within yourself. As a bonus action, you can spend 1 or more sorcery points to magically transform your body for 10 minutes. For each sorcery point you spend, you can gain one of the following benefits of your choice, the effects of which last until the transformation ends:

• You grow a fiendish tail with a stinger on it's tip, if you already have a tail it simply gains a stinger tip on the end of it, the stinger counts as a natural weapon and deals 1d8 piercing damage on a hit and has the reach property. 
• You grow fiendish wings, gain a flying speed equal to your walking speed, and you can hover.
• Each of your hands transforms into a fiendish claw, which you can use as a weapon if it’s empty. It deals 1d6 slashing damage on a hit.
• You gain darkvision out to 60 feet, this darkvision is not impeded by magical darkness.

Archfiend Exaltation

18th-level Fiendish Soul feature

Your powers from your fiendish blood have reached their peak, making you almost like an archfiend among fiendish blooded mortals.

You gain the following benefits:

• You gain immunity to poison damage and the poisoned condition.
• You gain immunity to bludgeoning, piercing, and slashing damage from nonmagical weapons.