Needler

The body of a wealthy merchant is found on 3rd floor of a luxury inn, not a mark on his body to suggest any foul play. The crownsguard are left with no option but to claim natural causes. A hooded figure slinks away, content with their work. They opens a small leather satchel and places 5 large needles into their respective grooves. 

The figure makes their way to the dilapidated part of town and notices an old man struggling to carry his stock. The figure offers the old man an unorthodox treatment for his pain, and lays out their needles once again. By carefully blocking pain, releasing the tension and allowing the old man's ki to flow the figure is able to completely rid the old man of suffering.

The Needler is a rogue who gives and takes pain where they see fit. By studying the bodies of their patients, or victims, they are able to precisely puncture the meridians in a body to inflict or remove pain. 

Meridian of Vitality

Starting at 3rd level, As an action, if a creature is within touch range, you may insert a number of needles up to and equal to your sneak attack die into the creature. The amount of Needles used by your Meridian of Vitality are taken away from your sneak attack damage this turn, if any. Each needle heals the creature for 1d6 if that creature has blood. You may remove the needles from the creature as a free action. You may use this ability a number of times equal to your intelligence modifier (minimum of one).  Your recover 1 charge of Meridian of Vitality after a short rest and all charges after a long rest. 

Needlecraft

When you choose this archetype at 3rd level, You gain proficiency with Needles. Needles are considered light, finess weapons and deal 1 flat damage+dex on a hit. When you successfully hit with a needle attack, the targets speed is reduced by half. Needles can be thrown 15ft. Needles are a common resource and can be found in almost every town. 

Puncturist

At 9th level, The first time you hit with a needle weapon attack on your turn, you may attack the same target again with a needle weapon attack as a free action. 

Pin Cushion

Starting at 13th level, you excel at inflicting pain and relieving pressure.

When you use your Meridian of Vitality feature on your turn, you may make one needle weapon attack.  Additionally this attack can use your entire sneak attack damage. 

De-qi

Starting at 17th level, you can strike with astonishing precision. When you hit a creature with your sneak attack using needles, the target makes a constitution saving throw against 8+int+ your proficiency. If the target fails they are paralyzed until the end of their next turn.