You can see in dim light within 60 feet of you as if it were bright light, and in Darkness as if it were dim light. You can’t discern color in Darkness, only shades of gray.

 You have proficiency in the Intimidation skill.

You cannot be killed by decapitation. You may attach or detach your head at will. You always know the distance and direction to your head unless it is on another plane.
Damage done to your head when seperated reduces your hit points. When separate, only your head can see and hear. Your headless body has a Blindsight of 20 ft. and cannot speak, but can cast spells, even spells with verbal components, as long as jour head is within 60 ft. of you.

You know the thaumaturgy cantrip. Once you reach 3rd level you can cast 'find steed' once per long rest. The mount conjured is considered a fey creature. Additionally the steed can be stored in your shadow as an action and can be retrieved as a bonus action. Once you reach 5th level you can cast 'knock' once per long rest.

You have vulnerability to bludgeoning, piercing, and slashing damage from gold plated weapons. You can´t carry any form of Gold, and grow nervous when in proximity of Gold. Your prefered method of payment is Gemms or Magic-items.

You have advantage on saving throws against being charmed, and magic can’t put you to sleep.

You don’t need to sleep. Instead, you meditate deeply, remaining semiconscious, for 4 hours a day. While meditating, you can dream after a fashion; such dreams are actually mental exercises that have become reflexive through years of practice. After resting in this way, you gain the same benefit that a human does from 8 hours of sleep.

Your Strength score increases by 2, and Charisma score increases by 1.

Like many fey, you are long-living. You reach maturity at 20 and reach old age after 400 years.

As death's heralds, dullahans generally do not pursue particular agendas. They tend towards true neutral

You are about the same size as a human. Your size is Medium.

Your base walking speed is 30 feet.

You can speak, read, and write Common and one extra language of your choice. Humans typically learn the languages of other peoples they deal with, including obscure dialects. They are fond of sprinkling their speech with words borrowed from other tongues: Orc curses, Elvish musical expressions, Dwarvish military phrases, and so on.