The Trigger

Creeping dread seizes the minds of many a tinkerer when the whispers start. First in dreams, then in their waking lives. If the whispers aren't answered; madness follows. After the completion of their hex gun, the mortal becomes an agent of their patron, the whispers that once emanated from their dreams now flow from the barrel of the gun itself. Provocateurs of destruction, these whispers almost always end in tragedy for the wielder of the hex gun, but not before they've left a trail of previously unimaginable violence in their wake.

Gunslinger

At 1st level, you gain proficiency with firearms and tinker's tools. When you complete a long rest you can invoke the power of your patron. When you do so you can create a number of bullets equal to your 10 + twice your warlock level. If anyone other than you tries to use a bullet created in this way, the bullet dissipates into smoke, and the person who tries to use it hears the collective screams of everyone your hex gun has ever killed.

Hex Gun

Also at 1st level, your patron imbues you with the knowledge necessary to create your hex gun. This magical firearm is a revolver of otherworldly design. You are proficient with your hex gun and you can channel spells through this hex gun, using it as an arcane focus. When you make a ranged weapon or spell attack roll while using this firearm, you gain a +2 bonus to the attack roll.

Wraith Shot

Starting at 6th level, your patron teaches you how to manipulate the life force of those you kill and weaponize it against your foes. When you reduce a creature to 0 hit points, you gain temporary hit points equal to your Charisma modifier + your warlock level.
     While you have any of these temporary hit points remaining and you deal damage to a creature, you can spend some or all of these temporary hit points to deal additional necrotic damage equal to the temporary hit points spent.

Eldritch Bullet

Starting at 14th level, your arcane power and your hex gun become perfectly intertwined. As a bonus action, you can charge your hex gun with arcane might. When you make a ranged weapon or spell attack, you can deal an additional 1d6 psychic damage on a hit until the end of your turn. You can use this ability a number of times equal to your Charisma modifier and regain all expended uses when you finish a short or long rest.

Expanded Spell List

The Trigger Expanded Spell List

Chambered Spell

Starting at 10th level, your hex gun becomes a receptacle for eldritch might. You gain an additional 2nd level spell slot. At level 12, it becomes 3rd level. At level 14, it becomes a 4th level spell slot.