Fell Born

Fell Born is a feat that entwines an adventurer's fate with the Shadowfell, transforming them into an entity forever bound to the plane's mysterious and dark aura. This connection bestows unique abilities while exerting the Shadowfell's ominous influence. The shadowy veil alters one's essence, offering dark resilience and the ability to return to the Shadowfell upon falling in battle outside its bounds, emphasizing the profound and eternal link.

• Cycle of Shadows. Upon dropping to 0 hit points outside the Shadowfell, instead of death, your body is pulled back across the veil, reappearing in a predetermined safe refuge within the Shadowfell. You must take a week to fully recover before returning to the Material Plane. Due to this connection you have disadvantage on Death Saving Throws while not in the Shadowfell.
• Shadow's Embrace. Once per short rest, you can blend with shadows, becoming invisible for up to 10 minutes or until you perform any aggressive action, such as attacking or casting a spell.
• Guardians of the Fell. When fighting in the Shadowfell to defend its lands from transgressive threats, you receive a +3 bonus to attack rolls and saving throws enhanced by the shadow energies flocking to protect their own.
• Increase your Intelligence, Wisdom, or Charisma score by 1, to a maximum of 20.
• If the banished spell is used on you, you return to your Shadowfell. If they are able to focus the whole 1 minute, you are stuck in the Shadowfell until you can find a portal back
• You take a -2 to an ability score of your choice.
• You loose a feat to gain this one. (DM's choice) 
• You have advantage on persuasion checks against undead.