The contents of this foul manuscript of ineffable wickedness are the meat and drink of those in evil’s thrall. No mortal was meant to know the secrets it contains, knowledge so horrid that to even glimpse the scrawled pages invites madness.

Most believe the lich-god Vecna authored the Book of Vile Darkness. He recorded in its pages every diseased idea, every unhinged thought, and every example of blackest magic he came across or devised. Vecna covered every vile topic he could, making the book a gruesome catalog of all mortal wrongs.

Other practitioners of evil have held the book and added their own input to its catalog of vile knowledge. Their additions are clear, for the writers of later works stitched whatever they were writing into the tome or, in some cases, made notations and additions to existing text. There are places where pages are missing, torn, or covered so completely with ink, blood, and scratches that the original text can’t be divined.

Nature can’t abide the book’s presence. Ordinary plants wither in its presence, animals are unwilling to approach it, and the book gradually destroys whatever it touches. Even stone cracks and turns to powder if the book rests on it long enough.

A creature attuned to the book must spend 80 hours reading and studying it to digest its contents and reap its benefits. The creature can then freely modify the book’s contents, provided that those modifications advance evil and expand the lore already contained within.

Whenever a non-evil creature attunes to the Book of Vile Darkness, that creature must make a DC 14 Charisma saving throw. On a failed save, the creature’s alignment changes to neutral evil.

The Book of Vile Darkness remains with you only as long as you strive to work evil in the world. If you fail to perform at least one evil act within the span of 10 days the book disappears. If you die while attuned to the book, an entity of great evil claims your soul. You can’t be restored to life by any means while your soul remains imprisoned.

Adjusted Ability Scores

After you spend the requisite amount of time reading and studying the book, one ability score of your choice increases by 2, to a maximum of 24. Another ability score of your choice decreases by 2, to a minimum of 3. The book can’t adjust your ability scores again.

Mark of Darkness 

After you spend the requisite amount of time reading and studying the book, you acquire a physical disfigurement as a hideous sign of your devotion to vile darkness. In order to comprehend the book's text, you slowly take on some physical attributes of the original author; Vecna. Attributes are as followed. 

1. The Eye of Vecna: Your all seeing eye makes you more alert to your situations around you. You gain a +1 to Armor Class. When attuned to the book, however, you are blind when you are more than 10 feet away from the item. 
2. The Hand of Vecna: You gain a sharp skeletal right hand. When you hit with a weapon attack, you take an extra 1d6 slashing damage. When attuned to the book, however, you deal 1d6 necrotic damage to all plants you touch that aren’t creatures.
3. The Aura of Vecna: You gain a glowing blue aura that outs you as a keeper of Vecna’s secrets. You have advantage on Charisma (Persuasion) checks made to interact with evil creatures and Charisma (Intimidation) checks made to interact with non-evil creatures. You are also immune to being  (charmed), being (frightened)and ([Tooltip Not Found]). When attuned to the book, however, all magic potions and holy water within 10 feet of you are negated of their magical properties. Likewise, every time you use the book, there is a 50% chance the spirit of Venca will try to control your spirit. If this happens and you do not make a constitution saving throw of 15, you become an NPC under the DM’s control. 

Command Evil

While you are attuned to the book and holding it, you can use an action to cast the dominate monster spell on an evil target (save DC 18). You can’t use this property again until the next dawn.

Dark Lore

You can reference the Book of Vile Darkness whenever you make a history check to recall information about some aspect of evil, such as lore about demons. When you do so, double your proficiency bonus on that check.

Dark Speech 

While you carry the Book of Vile Darkness and are attuned to it, you can use an action to recite words from its pages in a foul language known as Dark Speech. Each time you do so, you take 1d12 psychic damage, and each non-evil creature within 15 feet of you takes 3d6 psychic damage.

Destroying the Book 

The Book of Vile Darkness allows pages to be torn from it, but any evil lore contained on those pages finds its way back into the book eventually, usually when a new author adds pages to the tome.

If a solar tears the book in two, the book is destroyed for 1d100 years, after which it reforms in some dark corner of the multiverse.

A creature attuned to the book for one hundred years can unearth a phrase hidden in the original text that, when translated to Celestial and spoken aloud, destroys both the speaker and the book in a blinding flash of radiance. However, as long as evil exists in the multiverse, the book reforms 1d10 × 100 years later.

If all evil in the multiverse is wiped out, the book turns to dust and is forever destroyed.

Vile Apothos

This book contains the secrets of Lichdom. The ritual will show up in your notes, but is stated as followed. 

1. You must be a humanoid WIZARD of 17TH LEVEL or higher. 
2. You must construct and enchant a phylactery, or vessel to put your soul in. This phylactery can be any item, but it is recommended that it is of significant importance to the wizard. The phylactery will take 10 days to construct, and requires 500,000 gold. It must also be imbued with the soul of a powerful creature of good alignment. 
3. You must prepare a Potion of Lichdom. This potion must contain the blood of the creature you sacrificed, as well as enough poison to kill you. 
4. You must drink the potion, put your soul in the phylactery, and die.

Notes: Advantage: Persuasion, Advantage: Intimidation, Expertise: Intelligence Ability Checks, Bonus: Choose an Ability Score, Bonus: Choose an Ability Score, Bonus: Armor Class, Immunity: Charmed, Immunity: Frightened, Immunity: Disease, Blinded, Damage, Control, Buff, Debuff, Utility, Combat, Cursed