The Undying (Dripmarsh)

Death holds no sway over your patron, who has unlocked the secrets of everlasting life, although such a prize – like all power – comes at a price. Once mortal, the Undying has seen mortal lifetimes pass like the seasons, like the flicker of endless days and nights. It has the secrets of the ages to share, secrets of life and death. Beings of this sort include Vecna, Lord of the Hand and the Eye; the dread Iuz; the lich-queen Vol; the Undying Court of Aerenal; Vlaakith, lich-queen of the githyanki; and the deathless wizard Fistandantalus.

In the Realms, Undying patrons include Larloch the Shadow King, legendary master of Warlock's Crypt, and Gilgeam, the God-King of Unther.

This is a revamped version of the undying patron for a campaign a friend is running. 

Pact Magic

The Undying lets you choose from an expanded list of spells when you learn a warlock spell. The following spells are added to the warlock spell list for you.

Undying Expanded Spells

Spell Level	Spells
1st	Alarm, Zephyr Strike
2nd	Heat Metal, Locate Object
3rd	Spirit Guardians, Stinking Cloud
4th	Resilient Sphere, Phantasmal Killer
5th	Cloudkill, Reincarnate

Martial Prowess

Starting at 1st level, you gain a higher understanding of how to use weapons of war. You gain proficiency in Medium Armors and Martial Weapons.

Martial Body

Your body has adapted to the harshness of battle and you feel stronger when you kill an enemy. At 1st level, whenever you kill an enemy you are healed for half of the amount of damage you have dealt. 

Extra Attack

Beginning at 6th level, you can attack twice instead of once when you take the attack action on your turn.

Defy Death

Starting at 6th level, you can give yourself vitality when you cheat death or when you help someone else cheat it. You can regain hit points equal to 1d8 + your Constitution modifier (minimum of 1 hit point) when you succeed on a death saving throw or when you stabilize a creature with spare the dying.

Once you use this feature, you can’t use it again until you finish a long rest.

Undying Nature

Beginning at 10th level, you can hold your breath indefinitely, and you don’t require food, water, or sleep, although you still require rest to reduce exhaustion and still benefit from finishing short and long rests.

In addition, you age at a slower rate. For every 10 years that pass, your body ages only 1 year, and you are immune to being magically aged.

Indestructible Life

When you reach 14th level, you partake of some of the true secrets of the Undying. On your turn, you can use a bonus action to regain hit points equal to 1d8 + your warlock level. Additionally, if you put a severed body part of yours back in place when you use this feature, the part reattaches.

Once you use this feature, you can’t use it again until you finish a short or long rest.