One of your ancestors was renowned and feared for their mastery of the art of death.  As their descendant you have inherited their skill at ending lives.  Whether you follow or defy their legacy is up to you.

Bonus Proficiencies

At 1st level, you gain proficiency in Deception and Stealth.  If you are already proficient, you add double your proficiency bonus to any checks made with those skills.

Thrill of the Kill

Starting at 1st level, a delicious chill runs up your spine when you end a creature's life.  Once per turn, when you kill or reduce a creature to 0 hit points, you gain a Slayer die.  A Slayer die is a d4.  You can roll a Slayer die and add the number rolled to one ability check, attack roll, or saving throw you make.  You can wait until after you roll the d20 before deciding to use the Slayer die, but must decide before the DM says whether the roll succeeds or fails.  Once the Slayer die is rolled, it is lost.

You can have a number of Slayer dice up to your Charisma modifier (minimum one), but can expend only one per roll.  You cannot expend a Slayer die and a Bardic Inspiration or similar die on the same roll.  You lose any Slayer dice you have when you finish a short or long rest.

Ancestor's Strike

At 6th level, you can call on your deadly ancestor to aid in your attacks.  When you damage a creature you can see with a weapon or spell, you can make it take additional force damage equal to your Sorcerer level + 5 as a horrific specter of your progenitor appears and unerringly strikes the target with its trademark killing method. 

You can expend 1 or 2 sorcery points when you use this feature.  If you do so, it deals 5 additional damage per sorcery point expended.

If the attack or spell kills the target or reduces it to 0 hit points, the Slayer die you gain is a d6 instead of a d4.

Once you use this feature, you can't use it again until you finish a short or long rest.

Soul Sight

Starting at 14th level, you gain the ability to detect the souls or animating force of nearby creatures.  You automatically know the location of all creatures within 30 feet of you and can effectively see them.   Your ability to strike creatures is unaffected by spells and abilities like Blur and Mirror Image.

You know how many hit points creatures that you sense have and what type of creature they are (celestial, fiend, etc).

Killing Spree

Beginning at 18th level, you can merge with your ancestor to perform a revelry of slaughter.

When you kill or reduce to 0 hit points a creature using Ancestor's Strike, you can expend 1 sorcery point.  If you do so,  you can teleport up to 30 feet to a space you can see next to a creature.  The space you teleport to can be in the middle of the air or occupied, as you are briefly a ghost.   Your ancestor's spectral form overlaying your own, you together unerringly strike the creature, dealing your Ancestor's Strike damage.  As unusual, you can spend 1 or 2 sorcery points to increase the damage; however if you kill or reduce the creature to 0 hit points, you get another Slayer die (a d6).

If you kill or reduce the creature to 0 hit points, you can repeat this process as long as you keep spending sorcery points.  

After you finish your Killing Spree, you then teleport to any unoccupied space you can see within 30 feet of you.