Path of the King

Shotguns, chainsaws, and catchphrases.

This... is my BOOMER!

Beginning at 3rd level, you gain proficiency with firearms. Also, you treat shotguns as if they had the one-handed weapon property and you ignore their reload property.

Groovy

Starting at 6th level, you can go into a groove when you rage. If you do so, for the duration of your rage you can make a single ranged weapon attack with a shotgun as a bonus action on each of your turns after this one. You must use this attack on a creature within 5 feet of you. If you made a melee weapon attack this turn, this ranged weapon attack doesn't have disadvantage.

When your rage ends, you gain one level of exhaustion.

Swallow This

Beginning at 10th level, when you take the Attack action, you can make a special ranged weapon attack with a firearm you are wielding. As long as your firearm has two or more shots left, and you haven't made an attack this turn, you can fire two shots simultaneously at a creature as if it were a single-target attack. This attack deals an extra 2d8 of the weapon's damage type.

You can make this attack three times per short rest.

At Higher Levels. This extra damage increases by 1d8 when you reach 14th level (3d8) and 18th level (4d8).

Hail to the King, Baby

Starting at 14th level, whether through grit and determination or dumb luck, you continue to prevail over your foes. As stories of your victories spread throughout the Realm, people start to revere you and treat you like royalty wherever you go. Your confidence in battle is unparalleled and emboldens nearby allies. While raging, your Charisma Score becomes 24 and all friendly creatures within 10 feet of you, except yourself, have a +5 to melee damage with a Strength weapon.