The Banshee

You are of the lineage that is related to Banshees, your ancestors call to you investing their power within you.

Whisper in the Wind

You gain incorporeal movement you can move through other creatures and objects as if they were difficult terrain. You take (1d10) force damage if you ends your turn or run out of movement inside an object. 

Air Currents

At level 3, you become more like your banshee ancestors, you are now able to fly. Your flying speed is = to your base walking speed and can't increase via magic or feats.

Unseen

At 9th level you are able to become invisible at will, when you use this ability make a Dexterity (Stealth) check against any creatures Wisdom (Perception) actively searching for you, if you succeed you become hidden and cast invisibility on yourself. A creature that can see you can use its reaction to make this check fail. You may not use incorporeal movement while invisible and during combat this requires you to make a successful stealth check before you can become invisible.

Wailing Chords

At 9th level, your voice is able to be used to it's full potential. You gain the ability to release a mournful wail, provided that you aren't in direct sunlight. This wail has no effect on constructs or undead. All other creatures within 30 feet of you that can hear you must make a DC 13 Constitution saving throw. On a failure, a creature becomes incapacitated and must make the save again at the end of their next turns. On a success, a creature takes 3d6 psychic damage.

Close to Death (Platonically)

Starting at 13th level when you are making your death saving throws, you may add your intelligence modifier to the save.

Screaming Phantom

Starting at 17th level after you use your sneak attack on an enemy you can choose to immediately become invisible, using your reaction in the process.