Artificer Subclass: Gunsmith (Revised)
A master of engineering, you forge a firearm powered by a combination of magic and science.
Class Features
Master Smith
When you choose this specialization, you gain specialization with smith's tools and learn the Mending cantrip.
Thunder Cannon
At 1st level, you forge a deadly firearm using a combination of arcane magic and your knowledge of engineering and metallurgy. This firearm is called a Thunder Cannon. It is a ferocious weapon that fires leaden bullets that can punch through armor with ease.
You are proficient with the Thunder Cannon.
The firearm is a two-handed ranged weapon that deals 2d8 piercing damage. Its normal range is 150 feet, and its maximum range if 500 feet. Once fired, it must be reloaded as a bonus action. If you lose your Thunder Cannon, you can create a new one over the course of three days of work (eight hours each day) by expending 100 gp worth of metal and other raw materials.
Arcane Magazine
At 1st level, you craft a leather bag used to carry your tools and ammunition for your Thunder Cannon. Your Arcane Magazine includes the powders, lead shot, and other materials needed to keep that weapon functioning. You can use the Arcane Magazine to produce ammunition for your gun. At the end of each long rest, you can magically produce 40 rounds of magical ammunition with this magazine. After each short rest, you can produce 10 rounds. If you lose your Arcane Magazine, you can create a new one as part of a long rest, using 25 gp of leather and other raw materials.
Thunder Monger
At 3rd level, you learn to channel thunder energy into your Thunder Cannon. As an action, you can make a special attack with your Thunder Cannon such that it now does additional thunder damage as per the chart below.
| Level | Damage |
|---|---|
| 3rd | 1d6 |
| 5th | 2d6 |
| 7th | 3d6 |
| 9th | 4d6 |
| 11th | 5d6 |
| 13th | 6d6 |
| 15th | 7d6 |
| 17th | 8d6 |
Credit: http://www.giantitp.com/forums/showthread.php?367999-5e-Homebrew-The-Artificer-(of-Alancia)
Munitions Crafting
At 6th level, you've used your Thunder Cannon enough that you want to see what else you can get it to do. You begin to craft a variety of different ammunition to employ on the battlefield. You gain access to 2 of the following now, and an additional one at 9th, 14th, and 17th levels. If the munition requires an attack roll, use the same attack roll as you would for your regular shot. Each special munition can only be used once between a short or long rest. Some have level requirements noted in parentheses.
Blast Wave
As an action, you can make a special attack. Rather than making an attack roll, you unleash force energy in a 15-foot cone from the gun. Each creature in that area must make a Strength saving throw with a DC of 8 + your proficiency bonus + your Intelligence modifier. On a failed saving throw, a target takes 1d6 force damage and is pushed 10 feet away from you. This damage increases by 1d6 when you reach 9th(2d6), 14th(3d6), and 17th(4d6) levels in this class.
Alchemist's Wrath
You learn how to fill a delicate bullet with an acid that burns into your enemy upon impact. As an action, you can make a special attack. If the attack hits the target takes 2d6 acid damage. As you level up, you learn how to craft more potent acids that deal damage as per the chart below.
| Level | Damage |
|---|---|
| 6th | 3d6 |
| 7th | 4d6 |
| 9th | 5d6 |
| 11th | 6d6 |
| 13th | 7d6 |
| 15th | 8d6 |
| 17th | 9d6 |
Lightning Shot (Level 9)
You can now shoot lightning energy through your Thunder Cannon. As an action, you can make a special attack with it. Rather than making an attack roll, you cause the gun to unleash a bolt of lightning, 5-feet wide and 30-feet long. Each creature in that area must make Dexterity saving throws with a DC of 8 + your proficiency bonus + your Intelligence modifier. On a failed saving throw, a target takes 4d6 lightning damage. This damage increases at at 14th(5d6) and 17th(6d6) levels in this class.
Incindiary Round (Level 9)
You have imbued a bullet with a power such that it bursts into flames upon imact with its target. If your attack roll is successful then the target takes 2d8 piercing and 2d8 fire damage. The target must then make a Dexterity saving throw with a DC of 8 + your proficiency bonus + your intelligence modifier. On a failed saving throw, the target takes an additional 1d4 of fire damage every turn until they take an action to put the fire out. This increases by an additional 1d4 of fire damage at 9th(2d4), 14th(3d4), and 17th(4d4) levels in this class.
Explosive Round (Level 14)
You can channel fiery energy into your Thunder Cannon. As an action, you can make a special attack with it. Rather
than making an attack roll, you launch an explosive round from the gun. The round detonates in a 30-foot radius sphere at a point within range. Each creature in that area must
make a Dexterity saving throw with a DC of 8 + your proficiency bonus + your Intelligence modifier. On a failed saving throw, a target takes 4d6 fire damage. This increases at 17th(5d6) level in this class.
Tranquilizer Dart
If your attack roll is successful, the target must make a Constitution saving throw with a DC of 8 + your proficiency bonus + your intelligence modifier. If the target fails the saving throw, the target falls unconcious and do not wake until they succeed this saving throw. This saving throw is made by the target on their turn if in combat, and once every hour if outside of combat. If the target takes damage while sleeping they regain conciousness.
Scatter Shot
You have created a shell that, upon exiting the barrel of the Thunder Cannon, sends several small metal pellets out in a wide area. As an action, make a special attack. Any target within a 25ft cone must make a Dexterity saving throw with a DC of 8 + your proficiency bonus + your intelligence modifier. On a failed saving throw, the target takes 3d6 piercing damage if within 15 feet, and 2d6 if between 15 and 25 feet. This increases by an additional 1d6 of piercing damage at 9th(4/3d6), 14th(5/4d6), and 17th(6/5d6) levels in this class.
Credit: Hagshii01's alternate artificer class
http://homebrewery.naturalcrit.com/share/Bkclf0Mvx