Nighthunter

The earliest known Belmont was Leon Belmont, a former noble who had sought to rescue Sara Trantoul, his betrothed, from the clutches of Walter Bernhard, a vampire that kept his castle shrouded in eternal night. However, he was too late, as Walter had passed his curse on to Sara as part of his own game. With Sara infected, Leon was compelled to strike her down with an alchemical whip given to him by an ally, Rinaldo Gandolfi. Doing so unlocked the whip's full potential to deal mortal injury to vampires, thus becoming the Vampire Killer that would be passed through the generations of the Belmont family.

The trickery would not end with Sara's death. As Leon defeated Walter and was about to finish him off, his friend Mathias Cronqvist, who though supposedly bedridden had managed to inform Leon of Sara's kidnapping, appeared and used the powers of the Crimson Stone to steal the defeated vampire's energy. Angered at God for the death of his own love, Mathias had crafted a plan to not only steal Walter's power, but also entice Leon to his cause by setting up Sara's kidnapping and then convincing him to rescue her. Leon, however, disagreed entirely with Mathias, and rejected the offer of partnership. Mathias then turned on Leon and ordered his new ally Death to kill him. Leon succeeded in fending off Death, and in the end vowed that the Belmont clan would hunt the night.

Lustrate

Starting at the 3rd level you gain the ability to lustrate a weapon.

You gain proficiency in religion or alchemy tools.

Through the use of alchemy, baptism, and/or prayer you can lustrate a weapon, making it an instrument for destroying things that go bump in the night.  Once per long rest you can purify a weapon for killing monsters.  It is considered magical for the sake of overcoming resistances. 

Choose a creature type between aberration, fiend, monstrosity, or undead, the weapon deals an additional 1d6 radiant damage against creatures of that type. 

You can only lustrate one weapon at a time, if a new weapon is lustrated the previous one loses this effect.  

Alchemy Supplies

Gain Proficiency in Religion or Alchemy Supplies.

Religion

Gain Proficiency in Religion

Impalement Arts

As long as you are using a one handed weapon or a versatile weapon's one handed feature, and carrying no weapon or shield in your other hand, you can use your bonus action to draw a weapon and make a ranged weapon attack with it.  That attack must be done with a weapon with the thrown property. Throwing Holy Water uses your Proficiency + Dexterity modifier to hit.

Prepared for the Hunt

You can use 1 hour of your long rest to create simple throwing daggers with found materials such as wood, rock, or metal scraps.  While functional, they have no value to merchants and their improvised crafting fashion causes them to be destroyed on use.  You can make as many as your proficiency.

At level 15 you can make Handaxes or Holy Water or any combination of the 3 instead.

Flurry

Starting at the 7th level, after you make your first attack action, you can forgo your extra attacks to unleash a flurry on surrounding enemies.  All creatures you choose within range of your weapon attack must make a Dexterity save (DC is equal to 8 + your proficiency + either your strength or dexterity, which ever is higher) or take your weapon's damage.  This feature can be done whether the first attack hits or misses.  If you have more then 1 extra attack you can add a d6 to this damage for every extra attack forgone.

Hunter's Reflexes

At the 10th level you've honed your reflexes to avoid attacks.  When targeted with an attack, as a reaction you can move 5 feet in any direction.  If you move out of range of the attack it is negated.  This movement does not provoke attacks of opportunity.  This feature must be used before you know the results of the attack roll.

Tools of the Hunter

At the 15th level your mastery of the favored weapons of the Belmont clan becomes more apparent.  Whips you wield deal 2d4 damage instead of 1d4.  Additionally you can make simple handaxes or holy water with your prepared for the hunt.  

Opening Wounds

At the 18th level your attacks become brutally viscous as you focus down an enemy.  For each hit you land past the first with a slashing weapon on this turn causes the target to take an additional 1d6 slashing damage at the start of its turn.