Whispers of a powerful new weapon of fire and noise reached your ears and you had to seek their origins.  The reality of these firearms left you disappointed.  Slow to fire and difficult to aim, you still saw the potential in these dangerous tools.  After years of arcane research, you found the power you sought: binding your very soul to a warrior spirit.  With the aid and knowledge of other planes, you can bring the force of fire and thunder under your control to devastate your enemies.

Brimstone Loader

In your studies through the mystic and divine, you were able to forge a partnership with a supernatural entity that shares your drive for fire and noise.  The spirit of this creature can be summoned to your side, making your skills with your firearms more deadly.

Starting at 3rd level when you choose Arcane Gunner as a martial archetype, as a bonus action, you summon a fey or infernal spirit with a mental command that appears and floats behind your shoulder.  A good or neutral creature conjures the spirit of a sprite, evil creatures summon the spirit of an imp.  The spirit takes your fired gun, loads your firearm with supernatural speed, and returns it to your grip.  It conjures the bullet and gunpowder per shot, preserving your ammunition; in addition the shots the spirit loads are considered magical for the purposes of overcoming immunity and resistance as long as your loader is still summoned. If you drop your firearm, the spirit will catch it and carry it for you until you take it; if the spirit is carrying a firearm when the duration of this effect ends or is dismissed by you, it returns the weapon(s) to your inventory.

If you have two firearms of the same type, for example two rifles or two pistols, the spirit will load your second firearm as you attack and swap the fired gun with the loaded weapon, effectively removing the loading condition from firearms for the duration of this conjuration and allowing you to attack up to your normal amount of times per round.

The loader is incorporeal except in handling your firearms, and cannot be targeted by spells, attacks or damage; it can be visible or invisible, you decide when it is summoned.  The creature does speak common but does not act independently.  The spirit remains for one minute or until it is dismissed by you as a bonus action.  It can be suppressed by the effects of an antimagic field, dead magic area, etc.; if it is carrying your weapons when it is so affected, your firearms will drop to the ground in a space adjacent to you.

Can be summoned a number of times equal to your Intelligence modifier (minimum of 1); these uses recharge on a short or a long rest.

Bonus Proficiencies

Your studies have given you access to the tools and knowledge you need to make full use of smokepowder and steel.

Starting at 3rd level when you choose Arcane Gunner as a martial archetype, you gain weapon proficiency in Firearms, tool proficiency in Tinker's Tools and Alchemist's Supplies, and skill proficiency in Arcana.

Arcane Spotter

Your bond with your loader spirit has grown to the point where you can share its senses, giving you the ability to focus intently on a single target.

Starting at 7th level, while your loader is summoned you gain darkvision out to 60 feet.  If you already have darkvision, its radius is extended by 60 feet.

In addition, while your loader is summoned, as a bonus action on your turn you can select one target you can see; you have advantage against that target until the start of your next round.  Any attack against you has advantage until the beginning of your next turn.

Pull to Safety

Your loader can react to a threat against you to save its partner's life.  Using its own plane as a travel-way, it pulls you from the fray.

Starting at 10th level, while your loader is summoned, as a reaction to an enemy entering melee range of you, your loader can pull you though its plane to an unoccupied space within 30 feet of your original position that you can see.  Treat as the spell Misty Step with a casting time of 1 reaction.  Can be used 1 time per short or long rest.

Knockback Shot

Your focus with firearms has given you an unparalleled expertise and an ability to stop your enemies in their tracks as your attacks leave them writhing on the ground in pain.

Beginning at 15th level, when you hit with an attack from a firearm, you can force the target to make a Strength saving throw (DC=8+proficiency+INT modifier).  On a failed save the target is pushed back 5 feet and knocked prone, and its speed drops to 0 until the start of your next turn.

Partner in Arms

Your bond with your loader has grown to the strengths of eternal friendships, and you are now like two halves of the same whole.  Your loader spirit will now come to your side at your slightest whim or the smallest sign of danger.

Starting at 18th level, your loader can be summoned an unlimited number of times per short or long rest, and remains until dismissed by you.

Additionally, your loader spirit can now be summoned as a free action immediately after you roll initiative in combat.