Deadeye

Having learned the art of creating firearms and munitions you then turn your practice to dealing as much damage as you could to your chosen target. The Deadeye is a single-target killing machine. Your marked target is easier to hit, you are able to attack twice per round at higher levels, as well as being able to create and held into shadows while prone, the final feature of this subclass allows the Deadeye to unleash a three-round burst at the beginning of every encounter. 

Deadeye's Mark

Beginning at 3rd level you gain the ability to mark a target for death. A marked creature grants you advantage on attack roles and you now strike a critical blow whenever you role a 19 or 20. You cannot change your marked target until your current target is dead or incapacitated.

Your critical threat range decreases to 18 at 7th level, 17 to 13th level, and 16 at 17th level.

Skirmisher's Shot

Beginning at 9th level as a free action you can reload and fire a secondary shot that cannot critically strike but deals an additional 2d6 damage.

This damage increases to 3d6 at 13th level, and 4d6 at 17th level.

Three-Round Burst

At 13th level you have become a master of ranged warfare. On each of your first turns during encounters you can open the battle with three shots in rapid succession. Only the first shot would benefit from your Sneak Attack feature. The second shot deals an additional 2d6 damage, and the third deals an additional 1d6 damage.

Sniper's Cover

Beginning at 17th level you can project a 5 foot wide wall of shadows that absorbs projectiles while you lie prone. This wall also grants you advantage on stealth checks as well as a +5 modifier to your stealth check. This wall of shadow dissipates if you move from your position. You can only use this feature twice per long rest.