Shadowfell (5e Subclass)
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Rogues with a connection natural or otherwise with the Shadowfell enhance their skills with fell magics. Shadowfell rogues are typically shadar-kai, nocturne and undead who may or may not be servants of the Raven Queen sent to the Material Plane to take the souls and memories of creatures of interest.
Starting, at 3rd level, you gain the ability to step from one shadow into another. When you are in dim light or darkness, as a bonus action, you can teleport up to 30 feet to an unoccupied space you can see that is also in dim light or darkness. You then have advantage on the first melee attack you make before the end of the turn.
- Fell Recovery
Beginning at 9th level, your existence in a twilight state between life and death makes you difficult to defeat. When damage reduces you to 0 hit points, you can make a Charisma saving throw. The DC for this saving throw is equal to half the damage taken. On a success, you instead drop to 1 hit point. You can't use this feature if you are reduced to 0 hit points by radiant damage or by a critical hit.
After the saving throw succeeds, you can't use this feature again until you finish a short or long rest.
- Cloak of Shadows
By 13th level, you have learned to become one with the shadows. You can move your full speed without breaking stealth and when you are in an area of dim light or darkness, you can use your action to become invisible. Anything you are wearing or carrying is invisible as long as it is on your person. You remain invisible until you make an attack, cast a spell, or are in an area of bright light.
- Umbral Form
Starting at 17th level, you can take on a shadowy form as a bonus action. In this form, you have resistance to all damage except force and radiant, and you can move through other creatures and objects as if they were difficult terrain. You take 5 force damage if you end your turn inside an object.
You can remain in this form for up to 10 minutes. It ends early if you are incapacitated, if you die, or if you dismiss it as a bonus action. You regain use of this feature when you complete a long rest.