Fiendish Descendant

A Demon or Devil has left a mark on your very soul, whether from the day you were born, after an encounter or because of a curse that was broken before. The specific nature of your magic is determined by the type of fiend that affected you, whether it's the savage and brutal Demons, or the cunning and diplomatic Devils. In any of these cases, the mortals who see themselves gifted with these obscure powers have to choose a path, whether to rebel against the nature of their powers and fight for good, or give in to the origin of that magic and pursue their own wellbeing at the expense of everything and everyone else.

Cursed Origin

At 1st level, you choose a type of fiend: Devil or Demon, giving you different abilities and granting you the ability to speak Infernal or Abyssal.

Demon

 You gain resistance to fire and poison damage, as well as advantage on strength and constitution saving throws. You can read, speak and write Abyssal.

Devil

You gain resistance against psychic damage and advantage on saving throws against being charmed or frightened. You can read, speak, and write Infernal.

Dark Manifestation

Your hellish nature allows you to manifest aspects of the fiend your powers originate from.

Demonic Wrath

You unleash the wrath of the demons upon your enemies, infusing demonic energy into your spells and your weapons. Whenever you use this feature, once per turn, your spell or melee attack deals an extra 1d6 necrotic or fire damage (you decide whenever you activate this feature).

Whenever you use this feature, you physically manifest demonic attributes, which you can choose whenever this feature is activated and use your charisma modifier instead of strength for both attack and damage rolls.

Claws. Your hands turn into claws, with which you can make a melee attack for 1d6 piercing damage on hit, and you can make two attacks within the same action.

Horns. You grow demonic horns on your head, with which you can make a melee attack for 1d8 piercing damage on hit and, whenever you take the dash action and move at least 20 ft., you can make a melee action attack with your horns as a bonus action.

Hooves. Your feet temporarily turn into hooves, with which you can make a melee attack for 1d6 bludgeoning damage on hit, gain 15 ft. of extra movement speed, as well as a climbing speed equal to your movement speed.

You can use this feature a number of times equal to your proficiency bonus, and the effects ends after an amount of minutes equal to your proficiency bonus.

Devilish Pact

As a bonus action, you make a deal with a willing creature to protect them, giving you 1d4 temporary hit points for every deal made during combat. The creature in question loses that same amout of hit points, as it's the price for fulfilling their part of the deal made. You can choose from the following list of pacts:

Pact of Protection. Whenever the creature you made a deal with receives damage, you can reduce the damage taken by 1d6 hit points, as long as you're within a 15 ft. radius around them.

Pact of Revenge. The creature who receives the benefits of the pact chooses a creature when they make the deal, you get advantage on spell and melee attacks against that target.

Pact of Servitude. You can give the help action as a bonus action to the creature you made the deal with. Additionally, whenever you're within 15ft of said creature, its attacks deal an extra 1d6 necrotic damage.

Diabolic Surge

Starting at 6th level, your fiendish heritage grants you resistance to fire, necrotic and psychic damage, as well as some additional benefits, which depend on your Cursed Origin:

Demonic Infusion

While your Hellish Manifestation feature is active, the damage of your claw, horn or hooves attack counts as magical for purposes of overcoming resistances to nonmagical damage. You also beggin to steal the life force of your enemies, which causes you to regain d4 hit points for every enemy that is within a 10 ft. radius around you.

Devil Diplomacy

You gain proficiency in Charisma(Persuasion) and Wisdom(Insight) checks, as well as darkvision that allows you to see up to 120ft. both in magical and nonmagical darkness.

Occult Empowerment

At 14th level, your fiendish powers allow you to gain control over many different fiends or aspects of them. The nature of these benefits depend on your Cursed Origin.

Essence Corruption

While your Hellish Manifestation feature is active, when you hit a creature with a weapon or spell attack, you can use two sorcery points to attempt to corrupt the objective and make it hostile towards its allies. The creature must make a Wisdom saving throw, spending its next turn trying to attack its nearest ally on a failed save. You can use another sorcery point on the following round to extend this effect by one turn.

Fiend Manipulation

You can use your sorcery points to cast the Summon greater demon, Infernal calling, or Summon Fiend. The amount of sorcery points necessary is equal to the spell level at which you cast them (rounded up). When you cast any of these spells this way, the summoned fiends have disadvantage against saving throws against following your orders, and they gain the effects of your Devilish Pacts as long as they obey you.

Obscure Ascension

Beginning at 18th level, you can channel the dark presence of your fiendish ancestor, causing you to take on a physical appearance similar to that of your fiend type. As an action, you can use 6 sorcery points to activate this feature for 1 minute, obtaining 6d4 temporary hit points, as well as the following benefits, depending on your Cursed Origin:

Demon Form

Your presence becomes so densely obscure that it begins to corrupt the souls of others. Once you activate this feature, as an action, choose a number of creatures within 30 ft. of you and make them roll a DC Wisdom saving throw. On a failed save, their minds are corrupted by an uncontrollable rage, which makes them attack the creature that is nearest to them, break their concentration on spells, and suffer 4d12 psychic damage. On a successful save, they remain unaffected and suffer only half of that damage. This effect ends as soon as the duration of this feature is over.

Devil Form

You gain wings and a flying speed equal to your walking speed. Once this feature is active, choose up to 6 creatures you can see and make them roll a DC Wisdom saving throw. On a failed save, they're under your command for the duration of this feature, and remain unchanged on a successful one. They can repeat their saving throw at the start of their turns, or whenever they receive damage.