Boon of the Lulling Veil

Whispered dreams and the weight of eternity hang upon your mists, a smoke spun from the threads of the twilight realms itself. A single plum, a murmured phrase, and even the mightiest minds falter beneath the gentle embrace of you, the Dominion's Dream. Bestowed upon you by unseen hands of fate—or perhaps by the will of King Jaiden himself—the Lulling Veil is an echo of the changelings' rightful place in hierarchy amongst the stars. The mist is not merely inhaled but felt, seeping into the bone marrow and surface of those who resist, dissolving their will to a Dream that is indiscernable between fiction and reality. With enough exposure, creatures affected by the Veil welcome the mist to be woken up, to live in the Dominion's Dream.

You gain the changeling Shapechanger racial feature, able to change your appearance and shape at will as a free action once per turn. When a target passes a save against your sleep condition, or is immune to it, they take damage as a number of dice equal to your character level with a die size as their hit die size (or yours if it has no hit die like a custom monster) as they induce a sleep walk known as the Dominion's Dream, yearning to go to sleep. The damage type is dependent on your appearance:

Psychic - Simic Hybrid or Fallen
Magical Slashing - Leonin, Tabaxi, Garmr, Loxodon, Bugbear, etc. (Depending on what is most accurate)
Radiant - Aasimar
Magical Bludgeoning - Warforged
Dragon - Dragonborn or Au’Ra
Lightning - Genasi
Poison - Fairy
Fire - Tiefling
Cold - Goliath
Force - Human/Other
Magical Piercing - Leonin, Tabaxi, Garmr, Loxodon, Bugbear, etc. (Depending on what is most accurate)
Acid - Plasmoid
Thunder - Firbolg
Necrotic - Dhampir or Reborn

Your mist can only affect targets of your choosing, and you no longer need to expend bardic die to use your Trinan Technique. Instead, you can expend a bardic die to have the mists enhanced, coating caster attunements as well, and take effect on any attack or spell attack.