Zombie Lord's Crown: (Requires Attunement) Cursed Item: After attuning to this item and placing it on your head it cannot be removed except by a Remove Curse spell or other method of removing a curse which also removes your attunement to the crown. While you are alive the Crown grants you the Constitution and Intelligence of the undead. Your Constitution becomes Con:16 and your Intelligence become Int:3. You lose the ability to speak but can still understand languages you know. You also gain the following features/abilities 

Proficiency in Wisdom Saving Throws;

Damage/Condition Immunity-poison;

Darkvision-60ft;

Undead Fortitude: If damage reduces you to 0 hit points, make a Constitution saving throw with a DC of 5 + the damage taken, unless the damage is radiant or from a critical hit. On a success, you drop to 1 hit point instead.

If you die while wearing the crown you immediately reanimate as an undead version of yourself regaining the ability to speak. Your stats become the following; Str:16 Dex:10 Con:16 Int:13 Wis:12 Cha:8 You retain all previous features/abilities and also gain the following features/abilities:

Damage Immunity - Necrotic

Condition Immunity - Charmed

Undead Nature. You don't require air, food, drink, or sleep.

Stench. Any creature that starts its turn within 10 feet of the you must succeed on a DC 14 Constitution saving throw or be poisoned until the start of its next turn. On a successful save, the creature is immune to the your stench for 24 hours. Innate Spellcasting. Your spellcasting ability is Wisdom (spell save DC 12). You can innately cast the following spells, requiring no material components:

1/day each: animate dead, gentle repose

At lvl 10 your presence demands the respect of the dead and undead. You gain the following features:

Undead Master- You have a telepathic or mystical ability to converse freely with the living dead. Further, you can speak with the dead merely by touching a corpse.

Zombie Mastery. You can wrest control of zombies. When a zombie not under your control starts its turn within 10 feet of you, it must succeed on a DC 13 Wisdom saving throw or be subject to your mental commands, as if you had cast the animate dead spell.

If you die again the crown falls off your head, and you crumple into dust. If the curse is removed while you are undead you die. Only a wish spell can return you to life after you have died in this way.

Notes: Set: Constitution Score, Immunity: Poison, Immunity: Poisoned