Secret of the Firebrands

Murlynd speaks to you in dreams, whispering arcane alchemical formulae into your ears and granting you the ability to make and wield firearms.
Gunpowder is has not yet been discovered on Oerth, but, you know the secret to it.

• You gain proficiency with, and may purchase, Renaissance Firearms (which you call "firebrands") found the DMG, and in "Gunslinger: A Marital Archetype for the Fighter"  by Matt Mercer.  These weapons aren't widely available, but Murlynd's faithful keep a small underground market stocked up with the appropriate weaponry, which they sell only to other members of the faithful. 
• You may use your Divine Smite with ranged attacks with firearms.

• When you reach 3rd level, you may take the Sacred Oath of the Gunslinger; you become proficient with Tinker's Tools (Gunsmithing Tools), and may craft firearms and ammunition.