Thanks to your celestial eyes, you have Darkvision out to 120 feet, and can see through magical darkness as if it were dim light.

Divine Defiance:
Your divine essence cannot be forcibly reshaped. You are immune to spells or effects that would alter your form against your will (such as Polymorph, Curse of Lycanthropy, or True Polymorph, unless you allow it).

A spark of your divine origin still burns within you. Choose one divine trait:

Lightbringer:
You know the Light cantrip. Once per long rest, you may cast Sunbeam (6th level). Charisma is your spellcasting ability for it. This radiant beam bypasses resistance and immunity for fiends and undead.

Dread Seraph:
You know the Thaumaturgy cantrip. Once per long rest, you may cast Fear or Dominate Person (choose when you use the trait). Charisma is your spellcasting ability for these spells.

Heavenfall’s Wrath:
When you drop below 50% of your maximum hit points for the first time in a combat, your fallen power erupts. For 1 minute, you:

Deal extra radiant or necrotic damage (your choice) equal to your Charisma modifier on all weapon and spell attacks.

Emit an intimidating aura: enemies within 10 feet must make a Wisdom save (DC = 8 + prof + CHA mod) or be frightened until the end of their next turn.

Gain resistance to damage from celestial and fiendish sources.

Once used, this trait recharges after a long rest.

Voice of the Fallen:
You carry the weight of divine language. You have advantage on Charisma (Persuasion) and Charisma (Intimidation) checks against mortals and extraplanar beings. When speaking Celestial or Infernal, your voice can be understood by any creature with a language, as if under the Tongues spell.

Feature: As a bonus action, you can tap into your true demonic essence, transforming into a more powerful form. In this form, your physical features become more monstrous, with infernal traits like horns, wings, and glowing eyes. While transformed, you gain resistance to fire damage, +2 to your Strength and Constitution scores, and your unarmed strikes deal 1d6 additional fire damage. This transformation lasts for 1 minute, and you can use this ability once per long rest. In this form, your presence radiates an aura of intimidation; all creatures within 10 feet of you must succeed on a Wisdom saving throw (DC = 8 + your Charisma modifier + proficiency bonus) or be frightened until the start of your next turn.

Feature: You possess majestic, otherworldly wings, enabling you to soar through the skies with ease. You gain a flying speed of 60 feet. These wings are powerful enough to allow you to hover, maintaining your position in mid-air without difficulty. You can freely fly over difficult terrain, even in the presence of strong winds. You do not suffer the effects of the fly spell’s restrictions or other common limitations, such as being unable to fly through obstacles or areas with wind speeds that would normally cause flight disruption.

Feature: Despite your demonic nature, remnants of your former angelic grace still reside within you. Once per long rest, as an action, you can channel your angelic energy to heal yourself or an ally within 30 feet for an amount equal to twice your character level. Additionally, when you make a weapon attack, you can expend this power to smite an enemy with radiant energy. On a hit, the target takes an additional 2d6 radiant damage. If you deal radiant damage to a fiend or undead, the damage increases to 4d6.

Feature: Your form is fluid and malleable, allowing you to alter your appearance at will. As an action, you can change your physical appearance, including your features, voice, height, and weight. However, you cannot change your creature type, and your size remains unchanged. This transformation lasts for up to 1 hour, allowing you to blend into various environments or assume a different identity. After the transformation ends, you must finish a short or long rest before you can use this ability again. While shapeshifted, you retain all of your abilities, spells, and traits, including your voice for speech and spellcasting.

Feature: Your connection to the infernal realm grants you access to powerful demonic magic. You know the Thaumaturgy cantrip, allowing you to create minor magical effects. At 1st level, you also gain the ability to cast Hellish Rebuke once per long rest without expending a spell slot. At 5th level, you can cast Flame Strike once per long rest, representing your ability to call down fiery punishment from the depths of Hell. Your spellcasting is powered by your innate connection to the infernal realm, meaning your spells have an unsettling, otherworldly effect on enemies.

Feature: You can create perfect duplicates of yourself to serve as distractions, decoys, or agents of deception. As an action, you can create an illusory duplicate of yourself that lasts for 1 minute. This duplicate has no physical substance, but it appears identical to you and can mimic your movements. The duplicate cannot deal damage or cast spells but can move and act independently, creating the illusion of multiple Lucifers. Enemies must succeed on an Intelligence saving throw (DC = 8 + your Charisma modifier + proficiency bonus) to discern the illusion from the real you. You can use this ability once per long rest.

Feature: You are naturally gifted with music, whether it be through voice or instrument. You gain proficiency in one musical instrument of your choice. Whenever you make a Charisma (Performance) check using a musical instrument, you add your proficiency bonus twice. Additionally, your musical abilities allow you to charm, calm, or inspire others. When you play an instrument, creatures within 30 feet of you that can hear you must succeed on a Wisdom saving throw (DC = 8 + your Charisma modifier + proficiency bonus) or be charmed for 1 hour.

Feature: Your connection to music transcends mere performance, as you can use it as a conduit for magical energy. You can use a musical instrument as an arcane focus when casting spells, allowing you to channel your powers through music. When you cast a spell that requires a saving throw or an attack roll, you can choose to increase the saving throw DC or attack roll by adding your proficiency bonus to the roll if you are playing an instrument as part of the spellcasting.

Feature: Your skill with craftsmanship is unmatched, whether forging items of great beauty or magical significance. You are proficient with Smith’s Tools, allowing you to create or repair weapons, armor, and metal-based objects. You can also imbue objects with infernal power. When crafting a mundane or magical item, you can make the item resistant to fire damage or allow it to deal fire damage equal to your proficiency bonus when wielded.

Feature: Your connection to fire and the infernal allows you to manipulate flames with ease. You can cast Control Flames at will without expending a spell slot. At 3rd level, you gain the ability to cast Fireball once per long rest without expending a spell slot. You can also use this power to reshape and direct existing flames, creating barriers of fire or controlling their intensity.

Feature: Your demonic heritage grants you the ability to exhale a blast of intense fire. As an action, you can exhale a 30-foot cone of fire. Each creature in the area must make a Dexterity saving throw (DC = 8 + your Constitution modifier + proficiency bonus) or take 4d6 fire damage on a failed save, or half as much on a successful one. You can use this feature once per long rest.

Feature: Your physical strength is far beyond that of mortal creatures. You gain a +2 bonus to your Strength score, and your carrying capacity is doubled. When you make an unarmed strike, it deals 1d6 bludgeoning damage, and at 5th level, this increases to 1d8 bludgeoning damage.

Feature: You can open a portal to another plane of existence or a location you are familiar with. As an action, you can create a portal within a 10-foot cube. This portal allows you and any creature or object you carry to pass between locations. The portal lasts for 1 minute and can be used to access a different plane, teleport to a familiar location, or escape a dangerous situation. You can use this ability once per long rest.

Feature: Your mastery over space allows you to teleport instantly. As a bonus action, you can teleport up to 60 feet to an unoccupied space you can see. If you have seen the space before or are familiar with it, you can teleport there without needing to concentrate on its exact location. You can use this feature a number of times equal to your Charisma modifier (minimum of once). You regain all expended uses after a long rest.

Feature: You can create non-magical objects from nothing. As an action, you can conjure an object within a 3-foot cube, provided its worth does not exceed 100 gp. These objects are intangible, lasting for 1 hour before vanishing. You can create a number of objects equal to your proficiency bonus per long rest. This ability allows you to conjure tools, weapons, or mundane items.

Feature: Your control over the elements extends to water, enabling you to manipulate liquid at will. You can cast Shape Water at will without expending a spell slot. Additionally, you can control up to 10 gallons of water per long rest, either to create difficult terrain or to drown an opponent. Creatures in water under your control must make a Strength or Dexterity saving throw to escape or suffer disadvantage on Strength and Dexterity saving throws.

Feature: You are a master of physical combat, capable of holding your own in any fight. You gain proficiency with unarmed strikes, and your unarmed strikes deal 1d6 bludgeoning damage. At 5th level, your unarmed strikes deal 1d8 damage. Additionally, you have advantage on all Strength (Athletics) checks and Dexterity (Acrobatics) checks involving grappling.

Feature: You can speak without moving your lips, a skill honed to perfection. As an action, you can use your voice to cast Ventriloquism at will, allowing you to make your voice appear to come from any direction within 30 feet. This ability is useful for deception, distraction, or manipulation.