Aim Small Miss Small 2.0

As a trained and experienced adventurer you’ve learned where to target your weapon attacks to inflict the greatest results possible. You gain the following benefits:

• Once per your turn before you make an attack with a weapon (no spells) you can announce (must be stated before roll) you are targeting a specific location on an enemy's body for a designated effect below
• Roll the attack as normal. (Note: The attack must hit the target's AC, and still must meet the natural roll threshold for the called shot to be successful)
  1. Glancing Blow: Natural 16+ role (e.g., hand/foot/arm/leg, head/heart, eye/ear) inflicting -1d4 penalty to attacks and relevant skill checks, as well as one-half movement on the targeted creature until start of attacker's next turn
  2. Disarming/Hostage Rescue: Natural 17+, target drops weapon and has disadvantage on attacks until start of attacker's next turn
  3. Arrow to the Knee: Natural 18+ to reduce target's movement to 0 and disadvantage on their attacks for one minute
  4. Instakill: Natural 19+ to hit and instantly kill a targeted opponent with applicable saving throw
• You must call the shot and effect you want OUT LOUD before the attack roll - You cannot inflict an effect like lethal damage if you didn't announce your intention to inflict it
• If you have advantage/disadvantage on the attack roll normally you retain that advantage/disadvantage (e.g., Magical weapon property like Oathbow, Steady Aim, Attacking from concealment etc.)
• The targeted attack roll must not only hit (inflicting standard damage), but meet the minimum natural roll threshold to achieve the intended effect
• Successfully targeting of "Instakill" grants target Dexterity or Strength Save (depending on attackers weapon characteristics strength, slashing, dexterity piercing or finesse etc.) - DC=(Attacker's Proficientcy+(Dexterity or Strength Bonus)+Wisdom Bonus); Critical damage is imposed on a successful save and lethal damage on a fail (barring damage resistances/immunities or other feat/traits like "Interception," "Uncanny Dodge," "Cunning Action," "Evasion," or other defensive buffs) 
• Upon successfully achieving a called shot, if standard damage reduces target's hit points to 0 attacker may chose to do nonlethal damage instead (leaving target with 1HP) while still imposing desired effect, if called shot is unsuccessful target is killed 
• Critical fails on an attack roll may result in shots hitting the hostage, tripping if attacker takes movement on turn, dropping the weapon, breaking a bow string etc. at DM's discretion.