The first Witch Elves were Dawn Elf women who took up improvised knives to fight of their would be human conquers and violaters. These humans had posed as refugees towards the Dawn Elves their naive and out of touch nobility. Eventually the humans repaid their kindness by trying to conquer their lands with their large numbers. In their darkest hour, the Elven god of Murder was the only one to answer, and as such many barren of hightly devoted women pursue the path of slaughter. Worshipping their Murder god through bloodshed.

Murder Domain spells

You gain domain spells at the cleric levels listed in the Order Domain Spells table. See the Divine Domain class feature for how domain spells work.

Murder Domain Spells

Cleric Level	Spells
1st	divine favor, shield of faith
3rd	hold person, magic weapon
5th	elemental weapon, haste
7th	death ward, stoneskin
9th	circle of power, holy weapon

Bloodthirsty Zealot

Witch Elves fight with two cermonial Shortswords, carving a bloody path through their enemies. Witch Elves do not gain Destroy undead, but they do gain an extra attack at levels 5, 11, and 20. Witch Elves may not wear any armor, but in return they are protected by their gods divine power, and are under the effect of a permanent Mage Armor spell. In addition they gain Dueling Ace as a bonus feature:

Beginning at 1st level, when you willingly try to attack a target on your turn, you may begin dueling with them as a bonus action. All subsequent melee and ranged attacks, including targeted spell attacks, you make against a target you are dueling deal an extra 1d6 in damage. If a target you’re dueling takes any action except moving that does not target themselves or you, your targeted attacks against them get advantage on your next turn and you deal bonus damage equal to your proficiency bonus per hit. If you’re dueling and you attempt to attack another target, you immediately stop dueling the prior target. The dueling die changes as you gain levels, and starts at 1d6 bonus damage. This damage increases to 1d8 at level 7, 1d10 at level 13, and 1d12 at level 19. Dueling ends if you or the target are put into a dying state, rendered unconscious, or restrained.

Channel Divinity: Carnage is Magic

Starting at 2nd level, you can use your Channel Divinity to cast an additional spell per turn.

As you use your Channel Divinity, you may expend one of your spells slots to be able to cast a bonus spell of your choosing from the Cleric and Wizard spell list, provided it is of the same level. This spell may be cast as a bonus action in addition to all your normal actions.

Murderous Mastery

Beginning at 6th level, when a Witch Elf deals the killing blow to an enemy, she activates her Murderous Prowess racial trait until the end of her next turn. When activated in this way, she may gain it multiple times per battle, and it will not count towards her normal use of Martial Prowess. 

Madness of the Murder god

At 8th level, your ceremonial Shortswords are infused with the Madness of your Murder god. Any enemy that has been dealt damage by them must make a Wisdom saving throw at the end of your turn. The DC for this saving throw equals 8 + your Charisma modifier + your proficiency bonus. If failed the target must attack you with his melee attacks until the beginning of your next turn, and has disadvantage on these attacks. The target will be immune to Charm effects for this duration, but if you have the "Favored by the Murder God" Feat you will gain Resistance against your opponents attacks. Once your foe has successfully saved against this effect once, he cannot be affected by it again for the rest of the battle. 

Avatar of Murder

At 17th level, you become a living avatar of your Murder god in battle. At the start of each of your turns, if you are at or below half your hit point maximum and have at least 1 hit point, you regain hit points equal to your Wisdom modifier (minimum of 1).