Planes sorcer

One of your ancestors were born in a different plane of existence whether that be the feywild, shadowfell, or one of the other inner planes you now have been granted a bit of that power through it manifesting in you 

Natural magic

The magic of another plane  is coursing through you allowing you to do even more magic. you have and expanded spell list (warlock archfey)

plane Walker

you are able to go into an in between plane of existence where you disappear from the material plane for up to one minute and as long as concentration is maintained. This ability allows you to still see but not interact with the material plane but people cannot see you or feel you and you can walk through objects or walls

Heart sight

The player touches a creature and magically knows the creature's current emotional state. If the target fails a DC 10 Charisma saving throw, the player also knows the creature's alignment. Celestials, fiends, and undead automatically fail the saving throw.

Mirror self

you spend 6 sorcery points  and your bonus action to amplify your plane magic and create a mirrored version of yourself that has 10 AC and 10 HP and as long as it survives every turn you can spend your bonus action to have your mirrored version do a normal action like attack (NOTE: if your mirrored version does a spell it still counts as you doing a spell and as such will take a spell slot)

Stronger mirror

For every sorcery point spent above 6 on mirror self your mirrored self gains 1 AC 

Beyond the grave

At 18th level when your reduced to exactly zero hit points your spirit goes into an in between plane  and you gain the ability to continue the battle like normal  with half your normal hit points and your AC+2. Monsters can still see and hit you but you can also fight back (NOTE: if you die in this form you automatically fail all of your death saves and your character dies)