The arcane firearms of Eberron, developed by House Cannith, are named after various celestial bodies. The Comet, is the equivalent to a pistol, and the Supernova is the equivanlent to a musket. While these arcane firearms are similar to renaissance weaponry, there are notable differences.

 

Arcane tinkerer

You gain this at 3rd level. In creating and maintaining your firearms, you gain proficiency in the Arcana skill and tinkerers tools, and in order to use them, you learn how to use firearms. Should a magical mishap occur, you need to roll an arcana check to understand the exact nature of the issue, and then a tinkerers tools check to fix it. Mechanically, whenever a magical mishap occurs, a DC of 30 is set for fixing the weapon. The arcana check reduces the DC by the amount of the check, which then aids the tinkerers tools check to fix the weapon.

 

 

Arcane Firearm properties

Re-Ignite: As opposed to guns in our world, Arcane firearms use dragonshard powder to utilise their powers. Each firearm has a set number of shots before needing to be re-ignited with more dragonshard powder.

Magical Mishap: When a natural 1 is rolled when firing an Arcane firearm, a magical mishap occurs. When this happens, roll on the Sorceror wild magic table to see what occurs, and roll a flat d20 to see the state of the firearm. On a 10 or higher, the weapon merely needs a tinker, and can be fixed with a bonus action. On a 9 or lower, the weapon is damaged and needs to be fixed as described in the Arcane Tinkerer feature.

Shot DC: Whenever an arcane shot feature requires a save the dc is 8+ Proficiency bonus+ int mod.

 

Arcane Barrel

You gain this at 3rd level.

The arcane barrel is what makes each user of arcane firearms unique. Each barrels are typically uniform in design, allowing them to be taken from old firearms and placed into new and perhaps more powerful ones. They represent their makers understanding of their weapons and techniques as well as being a source of pride for them. Before firing a firearm, a barrel has to be “loaded”. Loading takes a bonus action. When a barrel is loaded, the firearm deals damage based on the barrel and has a special effect associated with each barrel. You can only use the special effects of each barrel 1 per long rest. Each special effect requires 3 shots worth of dragonshard powder.

When selecting this class, you gain 2 barrel options and you then gain 1 additional option at 7th, 10th and 15th level.

Radiant Barrel: When loaded the firearm deals 1d10 radiant damage. Special Effect: You can use your action to fire a targeted burst of light to blind targets. You choose a point within 100ft, anything within 10ft of that target makes a constitution saving throw. On a fail they are blinded and take 3d10 radiant damage, on a success they take half damage and are not blinded.

Flame Barrel: When loaded the firearm deals 1d10 fire damage. Special Effect: You can use an action to fire a fireball spell at a point within range.

Frost Barrel: When loaded the firearm deals 1d10 cold damage. Special Effect: You can use an action to coat an area in ice. Choose a 10 feet cube within in 50ft, that area becomes difficult terrain for 1 minute as it is coated with ice, and anyone standing in the area takes 3d10 cold damage when used.

Lightning Barrel: When loaded the firearm deals 1d10 lightning damage. Special Effect: You can use an action to use the lightning bolt spell as per the spell.

Shadow Barrel: When loaded the firearm deals 1d10 necrotic damage. Special Effect: You can use an action to fire a Shadow shot at a target. If the shot hits, the target must make a strength saving throw. On a failure the target takes 3d10 necrotic damage and is grappled by their own shadow. At the end on their turns they may make a saving throw to escape the shadow. On a success they take half damage and aren’t grappled.

Force Barrel: When loaded the firearm deals 1d10 force damage. Special Effect: You can use an action to fire a small wall of force. The wall is 5ft high and 5ft wide, and can act as cover or as a blockage say, filling up a door. The wall only lasts for 5 minutes or until the barrel is switched out.

Weapon	Weight	Reignite	Creation cost	Range
Pistol	4lb	6	200Gp	30/90
Rifle	9lb	2	300gp	100/300
Musket	11lb	4	250gp	40/120

Flame Barrel

When loaded the firearm deals 1d10 fire damage. Special Effect: You can use an action to fire a fireball spell at a point within range.

Force Barrel

When loaded the firearm deals 1d10 force damage. Special Effect: You can use an action to fire a small wall of force. The wall is 5ft high and 5ft wide, and can act as cover or as a blockage say, filling up a door. The wall only lasts for 5 minutes or until the barrel is switched out.

Frost Barrel

When loaded the firearm deals 1d10 cold damage. Special Effect: You can use an action to coat an area in ice. Choose a 10 feet cube within in 50ft, that area becomes difficult terrain for 1 minute as it is coated with ice, and anyone standing in the area takes 3d10 cold damage when used.

Lightning Barrel

When loaded the firearm deals 1d10 lightning damage. Special Effect: You can use an action to use the lightning bolt spell as per the spell.

Radiant Barrel

When loaded the firearm deals 1d10 radiant damage. Special Effect: You can use your action to fire a targeted burst of light to blind targets. You choose a point within 100ft, anything within 10ft of that target makes a constitution saving throw. On a fail they are blinded and take 3d10 radiant damage, on a success they take half damage and are not blinded.

Shadow Barrel

When loaded the firearm deals 1d10 necrotic damage. Special Effect: You can use an action to fire a Shadow shot at a target. If the shot hits, the target must make a strength saving throw. On a failure the target takes 3d10 necrotic damage and is grappled by their own shadow. At the end on their turns they may make a saving throw to escape the shadow. On a success they take half damage and aren’t grappled.

Magic from Mayhem

At 7th level, when a magical mishap occurs, you can choose channel the explosive burst of magical energy into a shot. You make at attack with disadvantage against a target, and it counts as a critical on a hit. You then suffer the effects of a Magical Mishap and your Arcane Barrel is badly damaged and needs to be fixed as per the Arcane Tinkerer feature.

Spin the Barrel

At 10th level, you gain the option to Spin the Barrel as an action. Once per short rest, you can target up to a number of enemies equal to the amount to Arcane Barrels you have functioning , and make a number of shots equal to the number of Arcane Barrels you have functioning. You can spread the shots across as you like, for example making 1 shot each at 2 people and make 2 shots at a single person. After using this feature you suffer a Magical Mishap.

Superior Barrel

At 15th level, if you finish a short rest and have only 1 or less special effects from your barrels you regenerate 1 barrel's special effect.

Dragon Barrels

At 18th level, your mastery of your craft reaches its pinnacle. You gain access to your final Arcane Barrel, a Dragon Barrel. The dragon barrels are based off of the 3 Progenitor dragons, Eberron, Siberys and Khyber.

Eberron, the Dragon Between: When loaded the firearm deals 1d6 force damage and 1d6 cold damage. Special Effect: You can use an action to fire an Eberron Shot. Assisted by the world around you, you deal 4d6 force and 4d6 cold damage to your target, and regain that much HP.

Siberys, the Dragon Above:  When loaded the firearm deals 1d6 radiant damage and 1d6 lightning damage. Special Effect: You can use an action to fire an Siberys Shot. If the target of the shot has the capacity to cast spells, they take 3d10 radiant and 3d10 lightning damage, and if they cast a spell on their next turn, the spell is countered and they retake the damage.

Khyber, the Dragon Below: When loaded, the firearm deals 1d6 necrotic damage and 1d6 fire damage. Special Effect: You can use an action to fire a Khyber Shot. If the target has an intelligence of 3 or higher, and is not a fiend, they take 4d6 necrotic damage and 4d6 fire damage and are paralysed as they experience terrible images of the Khyber. At the end of their turns they can make an intelligence saving through to escape the paralysis. 

Eberron, the Dragon Between

When loaded the firearm deals 1d6 force damage and 1d6 cold damage. Special Effect: You can use an action to fire an Eberron Shot. Assisted by the world around you, you deal 4d6 force and 4d6 cold damage to your target, and regain that much HP.

Khyber, the Dragon Below

When loaded, the firearm deals 1d6 necrotic damage and 1d6 fire damage. Special Effect: You can use an action to fire a Khyber Shot. If the target has an intelligence of 3 or higher, and is not a fiend, they take 4d6 necrotic damage and 4d6 fire damage and are paralysed as they experience terrible images of the Khyber. At the end of their turns they can make an intelligence saving through to escape the paralysis. 

Siberys, the Dragon Above

When loaded the firearm deals 1d6 radiant damage and 1d6 lightning damage. Special Effect: You can use an action to fire an Siberys Shot. If the target of the shot has the capacity to cast spells, they take 3d10 radiant and 3d10 lightning damage, and if they cast a spell on their next turn, the spell is countered and they retake the damage.