Marksman adept

You have Marksman training that allows you to perform special combat Trick shots. You gain the following benefits:

• You gain proficiency with Firearms.
• You learn two trick shots of your choice from among those available to the Gun slinger archetype in the fighter class. If a trick shot you use requires your target to make a saving throw to resist the trick shot's effects, the saving throw DC equals 8 + your proficiency bonus + your Strength or Dexterity modifier (your choice).
• If you already have grit points, you gain one more; otherwise, you have one grit point. This point is used to fuel your trick shots. A grit point is expended when you use it.  You regain 1 expended grit point each time you roll a 20 on the d20 roll for an attack with a firearm, or deal a killing blow with a firearm to a creature of significant threat (DM’s discretion). You regain all expended grit points after a short or long rest