Crazed Hit Man

You are a sneaky, but crazed hit man, hellbent on slaying your targets in the most publically brutal fashion immaginable. Through your experience and training you can blend into a crowd only to pop out and brazenly strike down your target with a furious verocity. The fear in the eyes of those around your target fuel your depraved mind, feeding some carnal desire to see fear in the eyes of those around you. Making friends has always been difficult for you.

Bonus Proficiencies

When you choose this archetype at 3rd level, you gain proficiency in Stealth and Intimidation if you don’t already have it. Your proficiency bonus is doubled for any ability check you make that uses either of those proficiencies.

Assassinate

Starting at 3rd level, you are at your deadliest when you get the drop on your enemies. You have advantage on attack rolls against any creature that hasn’t taken a turn in the combat yet. In addition, any hit you score against a creature that is surprised is a critical hit.

Blend In

Starting at 9th level, you can unfailingly dissapear into a crowd at a moment's notice. You can take the hide action as a bonus action to dissapear into a crowd of people. Any attempts to spot you that rely on sight are made at disadvantage.

Trophy Killer

At 13th level, you gain the ability to strike fear into the heart of your target's allies. When you drop a enemy to 0 hit points, you may take a bonus action to remove a part of their body to wave in the faces of their aliies.
Each creature allied to the target you killed within 30 feet must make a contested Charisma saving throw against your (Intimidation) check or be frightened of you for 1 minute.

Twist the Knife

Starting at 17th level, you become a master of creating grevious wounds. When you attack and hit a creature that is surprised, it must make a Constitution saving throw (DC 8 + your Dexterity modifier + your proficiency bonus). On a failed save, the creature takes half that damage at the begninng of their turns for the next minute. At the end of each of it's turns it may attempt to save again. The effect ends if they succeed on a saving throw.