Anointed

This subclass pulls a whole lotta inspiration from u/ZimitriReindhart's "Night Hunter" homebrew class, which you should check out.

Those that are Anointed hail from a divine bloodline, and are typically the newest generation of a lineage of devout monster hunters, banishers of evil, or other similarly divine-minded folk, typically spawned off of the response of a victim to an act of great evil. Their duty, whether they like it or not, is to continue their family's unending quest to combat a seemingly equally unending opposing force, even if their arch-nemesis lay dead. They tend to bear their familial crest proudly on their clothing, which tends to draw the ire of those that want nothing to do with magic or the looming threat, for some believe that the continued existence of the families combating evil are the sole reason for why the evil keeps returning. A single weapon is usually passed down generation-to-generation in these types of families, with your Anointed Fighter being the newest heir to said creature-of-the-night-vanquishing tool. There are less than a dozen individuals in the world in this specific set of circumstances at any given time, which simply heightens the import of their quest.

They are the morning sun, come to vanquish this horrible night.

Labyrinth Delver
At 3rd level, your background as a hunter of evil has led you to an acute understanding of the design principles behind the underground dens that so frequently harbor said evil. Whenever in building interiors or underground spaces, you gain advantage on Wisdom (Perception) checks made to detect hidden features, Wisdom (Survival) checks, and you and your party cannot become lost by normal means while in these environments. In addition, you are accustomed to mapping out the interiors of such places, and can easily create a map of where you've been in said interiors while occupied with other non-combative tasks.

Relic Weapon
Starting when you choose this Martial Archetype at 3rd level, you gain the ability to channel your divine bloodline through an heirloom weapon. An heirloom weapon, or Relic Weapon, must be a weapon dealing Slashing or Piercing damage, and only one of the listed heirloom weapons can be used per family. This weapon can be an actual familial heirloom of yours, or you can create it through extreme divine circumstance, making you the first of your clan. You are technically attuned to your Relic Weapon, but it does not fill an attunement slot.

Your Relic Weapon counts as magical for the purposes of overcoming damage immunities and resistances and gains a +1 bonus to attack and damage rolls, increasing to +2 at 7th level and +3 at 15th level. When attacking with this Relic Weapon, you gain a bonus to your damage rolls once per turn as Radiant damage, as shown on the table below. This once-per-turn limit resets on the use of an Action Surge, allowing for two in one technical turn.

At your DM's discretion, magical properties may be transferred or combined into your Relic Weapon.

Subweapons
At 3rd level, you gain the use of a variety of secondary abilities, fueled by the pool of arcane power known as Hearts. You have a pool of Hearts equal to your Fighter level, and regain all Hearts after a long rest. You regain an amount of Hearts equal to your proficiency bonus after a short rest. You regain 1 Heart when landing a critical hit with your Relic Weapon or when killing an enemy of reasonable power, as determined by your DM.

Hearts can be spent to use the following subweapons. Higher tiers of subweapons technically don't have specific levels that they are unlocked at, but obviously cannot be used if they exceed your Heart maximum (level). At 3rd level, you gain two of the following subweapon options available. You gain an additional subweapon option at 10th and 15th level.

Subweapon functions that require saving throws have a DC determined by your Charisma modifier (8 + your Charisma modifier + your proficiency bonus).

Magic Dagger

 * Tier I: You imbue a dagger with the same ritual as your Relic Weapon. As a bonus action, you can throw your dagger at a target within 60 feet, flying unnaturally straight and leaving an arcane mirage after impacting, with the real weapon returning to your hand after attacking. The mirage crumbles into dust after a minute. This attack automatically hits unless blocked by the Shield spell or a similar effect, and deals 1d4 + your Charisma modifier magical Piercing damage on hit. Costs 1 Heart per dagger to a maximum of 3 Hearts, increasing the damage by 1d4 per.


 * Tier II: As a bonus action, you cause dozens of spectral daggers to project around you, forcing all hostile targets within 5 feet of you to make Dexterity saving throws, suffering 1d8 magical Piercing damage and being pushed back 5 feet on a failure and taking half damage on a success. Costs 2 Hearts.


 * Tier III: As an action, you cause a floating wave of spectral blades to hunt targets in a 60-foot-long line. The wave can snake to targets that are at least 10 feet behind the previous target, and cannot snake back towards you or directly sideways. Targets caught in this wave must succeed a Dexterity saving throw or suffer 8d6 magical Piercing damage, and half on a success. Costs 5 Hearts.

Holy Flame

 * Tier I: You imbue a crystal-glass bottle with the same ritual as your Relic Weapon. As a bonus action, you can throw the bottle on the ground at a point within 20 feet, filling a 10-foot line with blue-white holy flame. After throwing, the bottle recoalesces wherever you keep it, full of slightly less water. Until the start of your next turn, when a creature enters the flame’s area for the first time on a turn or starts its turn there, it must make a Constitution saving throw, taking 1d6 + your Charisma modifier Radiant damage and having their movement speed reduced by half until the end of their next turn on a failure and half damage on a success. Undead creatures have their speed reduced to 0 until the end of their next turn on a failure. Costs 1 Heart.


 * Tier II: As a reaction to a melee attack, you quickly splash holy flame in between you and the attacker. You gain +3 AC against the attack, and the attacker must make a Constitution save or be blinded until the end of their next turn. Undead creatures have disdavantage on this saving throw. Costs 2 Hearts.


 * Tier III: As an action, you cause a storm of holy water to appear in a 15-foot-radius, 40-foot-high cylinder centered on yourself. All hostile targets caught in the area must make a Dexterity saving throw, suffering 4d10 Radiant damage on a failure and half on a success. Creatures that end their turn in this area, or enter it for the first time, must also make this saving throw. Undead creatures have disadvantage on this saving throw. This storm lasts until the end of your next turn. Costs 5 Hearts.

Relic Fire

 * Tier I: As an action, you channel your holy energy through your Relic Weapon, causing a swathe of elemental fire to erupt from it as you swing. All creatures in a 15 foot cone originating from you must pass a Dexterity saving throw or take 3d6 Fire, Lightning, or Cold damage. They take half as much damage on a success. Costs 2 Hearts.


 * Tier II: You gain the ability to infuse your Relic Weapon with holy energy as a bonus action, causing it to erupt in elemental flames. Your weapon's reach increases by 5 feet and deals an additional 1d4 Fire, Lightning, or Cold damage on hit for 1 minute. Costs 2 Hearts.


 * Tier III: As an action, you consolidate your holy power through your Relic Weapon, causing a condensed sphere of energy to come forth and erupt in a space within 60 feet. Each creature of your choice in a 20-foot-radius sphere must make a Dexterity saving throw. A target takes 4d6 Fire and 4d6 Radiant damage on a failed save, or half on a success. Costs 5 Hearts.

Rosario

 * Tier I: You gain the ability to brandish one of your holy objects as a holy symbol, deterring and possibly vanquishing creatures of the night with a flash of holy radiance. As an action, you force all Undead, Fiends, and other hostile creatures that are evil in nature (at your DM's discretion) that can see or hear you within 30 feet to make a Wisdom saving throw. If the creature fails its saving throw, it suffers 3d6 Radiant damage and has its movement speed reduced to 0 until the end of its next turn. In addition, any Undead creature within range of this ability of CR 1/2 or lower is immediately disintegrated. Costs 3 Hearts.


 * Tier II: Same as Tier I, with Undead within range of this ability of CR 1 or lower being immediately disintegrated. Damage increases to 5d6. Costs 6 Hearts.


 * Tier III: Same as Tier I and II, with Undead creatures of your choice within range of this ability of CR 2 or lower being immediately disintegrated. Damage increases to 7d6. Range increases to 60 feet. Costs 9 Hearts.

Pocket Watch

 * Tier I: You imbue an ordinary pocket watch with the same ritual as your Relic Weapon, allowing you to slow time just enough to get a defensive edge. As a bonus action, you can take the Dodge action. In addition, your movement speed is increased by 10 feet until the end of your next turn. Costs 2 Hearts.
 * Tier II: Once per turn, you can use your pocket watch to slow your perceived time, granting you advantage on your next attack roll. Costs 2 Hearts.
 * Tier III: As a bonus action, you use your stopwatch to force time to slow for you, thus hastening your own actions. For 1 minute after use, you gain the effects of the Haste spell, without requiring Concentration or fatigue after use. Costs 7 Hearts.

Enchanted Sage

 * Tier I: You can imbue a bundle of fresh sage with the same ritual as your Relic Weapon. As long as the sage is on your person, you can use your bonus action to siphon vitality from the un-rotting sage, restoring 1d6 + your Charisma modifier hit points. Costs 2 Hearts.
 * Tier II: You can draw on the undying vitality of your enchanted sage as a reaction to being forced to make an Constitution, Intelligence, or Wisdom saving throw, gaining advantage on the roll. Costs 3 Hearts.
 * Tier III: You can pick a single leaf from your sage bundle as an action, with the leaf dematerializing into the essence of life. For the next hour after picking the leaf, the first time you drop to 0 hit points from taking damage, you instead drop to 1 hit point, with the effect ending. Costs 9 Hearts.

Bloodline Attunement
At 7th level, your bond with your Relic Weapon becomes further strengthened. You gain advantage on saving throws and checks made to avoid being disarmed of it. In addition, if you so choose, targets dealt damage by your Relic Weapon's Radiant damage of reasonable size must succeed a Strength saving throw or be knocked back up to 10 feet.

Divine Protection
At 10th level, you gain resistance to Radiant and Psychic damage. In addition, you gain resistance to Necrotic damage for 1 minute after using your Action Surge.

Morning Sun
At 18th level, your bond with your Relic Weapon becomes the strongest it can be. You can an additional +1 to attack rolls with your Relic Weapon, and once per long rest, you can use your bond with your Relic Weapon to enter a heightened angelic state as a bonus action. This form lasts for 1 minute, and grants you the following benefits: You gain one level of exhaustion after this effect ends.
 * Your movement speed is increased by 20 feet, and you can jump a vertical distance equal to half your ground speed.
 * Your Relic Weapon's additional Radiant damage applies every hit.
 * Successful hits with your Relic Weapon on targets vulnerable to Radiant damage automatically crit.

At the DM's discretion, you may need to defeat the lingering spirit of the previous wielders of your Relic Weapon in order to gain this ability.

''"I see. Give him this message: You have become a cursed being and I will never forgive you. This whip and my kinsmen will destroy you someday. From this day on, the Belmont Clan will hunt the night." -レオン・ベルモンド''