Written by numerous authors, including devils, demons, and hags, this tome with parchment pages made out of dried humanoid flesh lists the appropriate steps for someone with the Spellcasting or the Pact Magic feature to become a lich.

This tome absorbs any soul of a creature that dies within 30 feet of it. In its presents, plants and trees rot away and the soil they were rooted becomes sterile.

A creature attuned to the book must spend 80 hours reading and studying it to digest its contents. The creature can then freely modify the book's contents, provided that those modifications advance evil and expand the lore already contained within. The creature can then perform the ritual and achieve lichdom.The manual then loses its magic, but regains it in a century.

After finishing reading the book, the attuned creature must make a DC 17 Charisma saving throw. On a success, the creature takes 42 (7d10) psychic damage. On a failed save the creature becomes mad and incapable to complete the ritual due to gaining the following madness effects:

• The creature experiences vivid hallucinations and has disadvantage on ability checks.
• The creature feels compelled to repeat a specific activity over and over. In this case, they can't stop reading repeately the Manual of the Lichdom.
• The creature gains the following flaw: "I am the only one that must know of the secrets of the Manual of Lichdom, and I must have the ritual perfectly memorized before I contact it."

Random Properties. The Manual of Lichdom has the following random properties:

• 3 minor beneficial properties
• 1 major beneficial property
• 3 minor detrimental properties
• 2 major detrimental properties

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.

Command the Undead. If you have succeed on the Charisma saving throw after reading the manual, you can animate up to 10 skeletons and/or corpses within 120 feet you. They use the skeleton and the zombie stat block respectively. Also, as an action, you can target up to 5 undead creatures you can see within 30 feet of you. The targets must make a DC 17 Wisdom saving throw. On a failed save, the targets must obey your commands for the next 24 hours, or until you use the first feature of this ability.

Completing the Ritual. After reading the manual, the ritual takes 1 minute to complete. If you die before the minute passes, your soul is claimed by the manual and you cannot be brought back to life. If the ritual is successful, you gain the following benefits:

• Your creature type changes to undead, if it wasn’t already.
• You gain immunity to poison, bludgeoning, piercing, and slashing damage from nonmagical attacks.
• You gain resistance to cold, lightning, necrotic damage.
• You gain truesight to a range of 120 feet.
• You gain the feature Legendary Resistance which you can use three times, and once you have, you can’t use it again until the next dawn.
• During the ritual you created a phylactery, as long as it is intact, once you die you gain a new body in 1d10 days, regaining all of your hit points and becoming active again. The new body appears within 5 feet of your phylactery.

Destroying the Manual. The Manual of Lichdom 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.

Notes: by a spellcaster