Dead Lands Patroller

The great war between the United Broods of Draconia and the Union of Gnomish Republics was fought with the most terrible weapons ever devised, negative energy bombs. How they affected the United Broods of Draconia is unknown, but the bombs turned the Union of Gnomish Republics into a blasted wasteland infused with negative energy. The victims of the bombs, and all who die in these lands rise again as undead. The only survivors were those who had made it into the great underground vaults before the bombs fell. These vaults are now the only source of enchanted weapons left, and the warring nations outside the dead lands are desperate for them. The trade routes are kept open only by the valor of the patrollers that set out from both the vaults and living nations, braving the fearsome storms, the shambling zombies, the wraith filled cities, the persistant negative energy background radiation, and the skeletal remains of the Union of Gnomish Republics army. 

Experience in the wastes

At level 3 the character gains the following:

1. Resistance to necrotic damage. Whether by long exposure to the background necrotic energy of the dead lands or exposure to the amulets that protect from that energy, the character is now resistant to necrotic damage

2. Proficiency with Laser Rifles, Pistols, and Anti-mater rifles. Experience in combat with these weapons and friendly contact with the gnomes that carry these as their standard kit has made you familiar with how they work. Note: Gnomes who were raised in the vaults would start at level one with proficiency in these weapons. Instead, they can treat any laser weapons they use as having an additional +1 effect. For example, a normal laser rifle would be considered a +1 laser rifle, and a +1 laser rifle would be considered a +2 laser rifle when used by this character. 

Ambush the ever vigilent

At level 7 all undead have disadvantage on perception checks to detect you and characters you choose within 30 feet of you.

Cut their strings

At level 11 you can channel divinity as if you were a cleric with a level equal to level in ranger. The only option you can use with that channel divinity action is to Turn undead.

Don't get close

As an action, you can infuse a piece of ammunition with the ability to turn undead by expending a channel divinity use. The ammunition stays infused until you complete a long rest. When fired Turn undead from the point of impact rather than from the character.