Sniper

Rogues are known to specialize in being quiet killers no one notices. They have a large toolkit and know how to use it. But Snipers specializes in a brand new weapon: The Firearm. While most rogues shake their head at such a big weapon that alerts the entire village to their location on use the sniper sees it as the most effective way to kill the enemy. They can take out their target from a thousand feet away if they need to.

Scavenger for Guns

Upon choosing this archetype at 3rd level, you gain proficiency with Tinker’s Tools. You may use them to craft ammunition at half the cost, repair damaged firearms, or even draft and create new ones (DM’s discretion). However, as a Sniper, you tend to use weapons other's have made. This generally means you've stolen them.

Firearm Properties

Firearms are a new and volatile technology, and as such bring their own unique set of weapon properties. Some properties are followed by a number, and this number signifies an element of that property (outlined below). These properties replace the optional ones presented in the Dungeon Master’s Guide. Firearms are ranged weapons.

Reload. The weapon can be fired a number of times equal to its Reload score before you must spend 1 attack or 1 action to reload. You must have one free hand to reload a firearm.

Misfire. Whenever you make an attack roll with a firearm, and the dice roll is equal to or lower than the weapon’s Misfire score, the weapon misfires. The attack misses, and the weapon cannot be used again until you spend an action to try and repair it. To repair your firearm, you must make a successful Tinker’s Tools check (DC equal to 8 + misfire score). If your check fails, the weapon is broken and must be mended out of combat at a quarter of the cost of the firearm. Creatures who use a firearm without being proficient increase the weapon’s misfire score by 1.

Explosive. Upon a hit, everything within 5 ft of the target must make a Dexterity saving throw (DC equal to 8 + your proficiency bonus + your Dexterity modifier) or suffer 1d8 fire damage. If the weapon misses, the ammunition fails to detonate, or bounces away harmlessly before doing so.

Ammunition

All firearms require ammunition to make an attack, and due to their rare nature, ammunition may be near impossible to find or purchase. However, if materials are gathered, you can craft ammunition yourself using your Tinker’s Tools at half the cost. Each firearm uses its own unique ammunition and is generally sold or crafted in batches listed below next to the price.

Firearms

Name	Cost	Ammo	Damage	Weight	Range	Properties
Palm Pistol	50g	2g (20)	1d8 piercing	1 lb.	(40/160)	Light, reload 1, misfire 1
Pistol	150g	4g (20)	1d10 piercing	3 lb.	(60/240)	Reload 4, misfire 1
Musket	300g	5g (20)	1d12 piercing	10 lb.	(120/480)	Two-handed, reload 1, misfire 2
Pepperbox	250g	4g (20)	1d10 piercing	5 lb.	(80/320)	Reload 6, misfire 2
Blunderbuss	300g	5g (5)	2d8 piercing	10 lb.	(15/60)	Reload 1, misfire 2

Rifle

Crafted

10g (20)

3d6 piercing

25 lb.

(100/380)

Two-handed, misfire 6, reload 4

Sniper's Nest

You may set up a nest of ammo, defence and weaponry, allowing you to use your sneak attack damage on all ranged weapon attacks while in here. You still can only do it once per turn. You also have advantage to stealth while in here.

Setting up this nest takes a full turn. 

Lightning Reload

At ninth level your fingers can work a gun as easily as they can a lock. You can reload as a bonus action.

Unseen Assailant

Starting at 13th level, you are trained to remain unseen in battle. When you make a ranged attack while hidden – both unseen and unheard – you do not give away your position. Also, when you hide, you can also draw a firearm as one action or bonus action. Alternatively, you can reload when you hide as an action or bonus action. 

Button Mash

At 17th level, you can shoot faster than the eye can see. When you score a critical hit you can make extra attacks, equal to your rogue class level divided by 5 rounded down, as a bonus action.