The Empty

A paladin is not the only class that take an oath, nor is it the only one that can break one. The oathbreaker warlock subclass, the Empty, should hopefully satisfy all the needs you have for making a character that has broken their pact with their former patron in a sufficiently messy fashion.

Expanded Spell List

The Empty 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. Unfortunately, do to the constraints of DnDBeyond, I can't add Nathair's Mischief and Mordenkainen's Faithful Hound to the spell list since they are from licensed material. I recommend you add the spells to your spell list in some other way, or if you don't think your character will learn those spells, then don't bother.

Empty Expanded Spells

Spell Level	Spells
1st	bane, detect evil and good
2nd	nathair's mischief, silence
3rd	melf's minute meteors, nondetection
4th	freedom of movement, mordenkainen's faithful hound
5th	geas, hallow
8th	antimagic field

Patron's Curse

Starting at 1st level, you gain an aura of bad luck, causing all within a 15 foot radius sphere centered on you (including yourself) to suffer a 1d4 against all rolls made within. The dice rises to a d6 at 6th level, and d8 at 14th.

 

This aura is not visible or detectable to any form of sense, including truesight and detect magic. You can suppress the bad luck with an action, on subsequent turns you may concentrate (as though on a spell) to keep up the effect.

You will need to go back into the creator and change the aura that you want based on your level and whether it is suppressed or not. Currently, dnd beyond doesn't let me just make it a simple toggle for you.

Aura (14th level)

At 14th level, your curse reaches its final form, as you (and anyone in the aura) subtracts 1d8 from any roll they make.

Aura (1st level)

At 1st level, your aura subtracts 1d4 from any rolls you (or anyone in the aura) make.

Aura (6th level)

At 6th level, your aura increases in power as the curse your patron has inflicted upon you grows. You (and anyone in the aura) now subtract 1d6 from any roll.

Aura Suppressed

You are suppressing your aura. This effect requires concentration, similar to a spell.

Patron’s Enemies

You have advantage on charisma checks against enemies of your patron, as your name spreads far as wide as the traitor. Choose two of the choices offered to you in the Ranger’s Favored Enemy trait. 

If none of the options seem appropriate for your patron, work with your DM to come up with some other sufficient group that your reputation as an Oathbreaker would glean you support from.

I'm not entering in all of the options from the Favored Enemy list. You'll just need to keep track of that yourself, sorry. I'll go back and enter it if someone actually wants to play this.

Patron’s Brand

Starting at 6th level, you have figured out something of how your patron is keeping an eye on you, and can inflict it on another.

As part of a melee attack against a creature, on a successful hit, you cause your curse to emanate from your target instead of you. You must concentrate on this (as though it were a spell), and if the creature dies, the curse returns back to you.

Theft of Fire

Starting at 10th level, you manage to latch onto a piece of your patron’s influence left within you, and cause it to bloom. Choose one ability that would have been available to you under your previous patron at this level or lower. You now have access to that ability.

If the ability has some prerequisite that you do not meet (such as the Hexblade’s Curse for the 10th level ability Armor of Hexes), your DM may allow you to modify the ability in some manner that still allows you to gain the essential effect of the feature (such as substituting the Hex spell for the Hexblade’s Curse feature).

A Weapon to Surpass Metal Gear (Sorry, couldn’t come up with a better name)

The pact boon, the last remnant of your bond with your patron. Through the power you have amassed on this new path you’ve travelled, your boon has evolved a new power. Starting at 14th level, your boon improves.

• Pact of the Blade: Like the legendary Sword of Kas, which also was a boon of the bond between master and servant, your use of your weapon has become imbued with the capacity to end immortals. Any magic your weapon possesses can surpass antimagic and other effects that would achieve the same thing of suppressing its effect. Additionally, your weapon, no matter what it was enchanted with previously, also acts as though it was a {Weapon} of Certain Death. This also applies to any future weapon you cause to become your pact weapon.
• Pact of the Tome: Your tome has almost become an ally in some ways. With a semblance of your will imprinted upon it, your book becomes a sentient magic item, with mental stats equal to your own, only able to communicate via vague emotions. The book is able to assist you in the following way. Whenever you cast a spell that requires concentration, you can shift that burden to your book as long as it is on your person. The book can add your constitution saving throw modifier to its roll, but it is a creature, and so is affected by your bad luck if it is within the aura. Your book can do this an amount of times equal to your charisma modifier (minimum of 1) per long rest..
• Pact of the Chain: Your familiar has stuck by you through thick and thin, your bond becoming stronger than anything you had before you left your patron. You may cast Shapechange without any components, targeting your familiar as though they had cast it, but using your own level to determine its new form. After casting this, your familiar dies from the stress of the magic affecting it, and you cannot use this feature again for seven days.
• Pact of the Talisman: Your talisman has become a truly protective object, able to hide one from all gazes, even that of your patron. The wearer of your talisman can now become invisible as an action. Anything they are wearing or carrying is invisible with them. They remain invisible until the talisman is removed, until they attack or cast a spell, or until they use a bonus action to become visible again. Additionally, they are no longer affected by the bad luck of your curse.

Pact of the Blade

Like the legendary Sword of Kas, which also was a boon of the bond between master and servant, your use of your weapon has become imbued with the capacity to end immortals. Any magic your weapon possesses can surpass antimagic and other effects that would achieve the same thing of suppressing its effect.

Additionally, your weapon, no matter what it was enchanted with previously, also acts as though it was a {Weapon} of Certain Death. This also applies to any future weapon you cause to become your pact weapon.

Pact of the Chain

Your familiar has stuck by you through thick and thin, your bond becoming stronger than anything you had before you left your patron.

You may cast Shapechange without any components, targeting your familiar as though they had cast it, but using your own level to determine its new form.

After casting this, your familiar dies from the stress of the magic affecting it, and you cannot use this feature again for seven days.

Pact of the Talisman

Your talisman has become a truly protective object, able to hide from all gazes. The wearer of your talisman can now become invisible as an action.

Anything they are wearing or carrying is invisible with them. They remain invisible until the talisman is removed, until they attack or cast a spell, or until they use a bonus action to become visible again.

Additionally, they are no longer affected by the bad luck of your curse.

Pact of the Tome

Your tome has almost become an ally in some ways. With a semblance of your will imprinted upon it, your book becomes a sentient magic item, with mental stats equal to your own, only able to communicate via vague emotions. The book is able to assist you in the following way. Whenever you cast a spell that requires concentration, you can shift that burden to your book as long as it is on your person. The book can add your constitution saving throw modifier to its roll, but it is a creature, and so is affected by your bad luck if it is within the aura. Your book can do this an amount of times equal to your charisma modifier (minimum of 1) per long rest.