Order of the Yharnam Hunters

The Yharnam Hunters are a group of warriors who are dedicated to keeping their regions safe by hunting down beasts - or anything other than beasts if need be - that pose a threat. Hunters are agile fighters armed with a trick weapon, a transforming melee weapon in the right hand, and a firearm in the left. They do not employ shields, but rather take advantage of their mobility in order to avoid attacks. It is believed that the Hunters started out as a branch of the Healing Church very much like The Choir. This would mean that, at least in Yharnam, Hunters were recruited by either Gehrman or the Church itself.

Paleblood Blessing

Starting when you choose this archetype at 3rd level, you gain immunity to disease and the ability to ingest the blood of your foes to heal yourself. You have 1 blood vial, which you can ingest as a bonus action to regain hit points equal to your hemocraft die plus half your Blood Hunter level (rounded down) and gain advantage on constitution saving throws for 1 minute. You regain used blood vials after finishing a long rest.

The amount of vials you have increases by one at 7th, 11th, 15th and 18th level.

Hunter's Training

Starting when you choose this archetype at 3rd level, you train in the ways of creating trick weapons, using firearms, a Hunter's Bane extension to monstrosities and aberrations, and using Blood Echoes, which are "the Bloody memories of those cursed by the plague of the Beast".

You gain proficiency with Tinker's Tools and the ability to create trick weapons; these weapons can be transformed into alternate forms and have different attacks in their transformed mode. In order to create a trick weapon you must choose two different weapon types to use for  it, and costs an amount of gp worth the weapons plus 50 gp for a workweek to create them.

 You gain proficiency with using firearms and can create them just like the Gunsmith feature from the Gunslinger.

Your Hunter's Bane feature now extends to Monstrosities and Aberrations.

You gain a number of Blood Echoes equal to your Blood Hunter level which can be spent using these options:

Transforming Attack. As part of an attack you can spend 1 Blood Echo to transform your weapon if it is a trick weapon.

Parrying Shot. As a reaction, you can use 1 Blood Echo and fire a firearm shot in an attempt to parry a melee attack. Make a ranged weapon attack with the DC being the target's attack roll. On a success, the target takes half of the damage of the firearm, and is stunned until the end of your next turn. 

Heavy Attack. As an action, you can spend 2 Blood Echoes and attempt to hit a target with a heavy attack. Make a melee weapon attack, on a hit the target takes an additional damage die worth of damage. Additionally, if the target is flanked and the attack hits, the target is stunned until the end of their next turn.

At 7th level, you gain Quickstep.

Quickstep. As a reaction, when a creature targets you with an attack, you can spend 2 Blood Echo to move 5 ft. in any direction and imposes disadvantage on the attack targeting them.

Hunter's Agility

At 7th level, you can now Dash, Dodge, or reload a firearm as a bonus action.

Evasion

At 11th level, your instinctive agility lets you dodge out of the way of certain area effects, such as a a beast's pounce or a shockwave. When you are subjected to an effect that allows you to make a Dexterity saving throw to take only half damage, you instead take no damage if you succeed on the saving throw, and only half damage if you fail.

Hunter's Brand

Also at 11th level, your Brand of Castigation now seeps into the very essence of your foes, slowing their movements and attacks. Whenever a creature afflicted by your brand attempts to move, they must roll a Constitution saving throw or their movement speed is reduced to 0. Additionally, if they attempt to attack you, they must roll a Wisdom saving throw. On a failed saving throw the creature is stunned until the next attack that hits. Aberrations and Monstrosities make this saving throw with disadvantage.

Rally

At 15th level, you can regain recently lost health by damaging enemies. When you damage a creature in any way, you restore a half of health lost between your last turn and now. If you have advantage on the attack, you instead regain all lost hit points. You cannot regain health from damage done by your Blood Curses or Crimson Rite feature.

Visceral Attack

At 18th level, you have gained the ability to exploit an enemy's defenseless state. On your turn, you can use your action to make a visceral attack against a target that is stunned or paralyzed and is within your melee range. Make a melee attack roll plus your Dexterity modifier and proficiency bonus. On a hit, the target takes 10d8 necrotic damage, is knocked prone, and the stunned or paralyzed condition is removed