d100 Worst Books in the World

d20 Book Form
01 Engraved leather bound book with painted vellum pages
02 Leather scrolls made from pterodactyl skin in bone tubes
03 Clay tablets packed in wooden chests
04 Collection of painted bark sheets in a trunk
05 Carved wooden slats in a wooden case
06 Brass engraved plates in various shapes stacked in boxes
07 Set of vellum scrolls in tubes in a wooden casket
08 Demon skin leather book with great puree iron nails on spine
09 Devil hide leather book with silver nails on spine
10 Dragon skin book with scaled leather sheets
11 Other monster skin cover with vellum sheets
12 Living flesh book of alien planar being
13 Birch bark sheet books with animal hide covers
14 Bound collection of rubbings from ancient cave with printed leather cover
15 Illuminated book with complex hand painted artworks
16 Bound book of human skin leather binding with vellum pages and tattooed text
17 Metal brass plate bound book with gems and fanciful calligraphy
18 Wood and leather covered book with block printed
19 Clay shards of ancient tablet with dense tiny text in a wooden case
20 Stamped gold foil sheets in reliquary box

d20 Book non magic features

01 Gems embed in cover worth several thousand
02 Gold leaf in artwork and text
03 Feature artwork by great artist
04 Hand print or claw mark from some monster damaging book
05 Bloodstains spattered on book or written in blood
06 Several complex locks d4+1
07 List of signatures of mighty wizards from over the ages who owned the book
08 Most copies are flawed translations or damages and incomplete
09 Inquisitors seize all known copies and execute any one with such a book
10 Book in poor condition, moving it or even reading it might damage or destroy it
11 Book survived severe damage and some content might be recoverable
12 Book is in several pieces and other fragments need to be assembled to fully use
13 Book covered in deadly spores causing mummy rot if read and a save failed
14 Powerful immortal wizard (or lich) craves the book
15 Book has footnotes and is a scholarly edition in ancient languages 
16 Poisonous ink save vs poison each use or wear gloves
17 Book is worshiped by a cult who want it to worship
18 Book full of commentary added by a later writer with extra content
19 Book advises to call specific demons and provides their secret names
20 Complex mechanical puzzle lock with deadly poison traps

d20 Book Magic Features
01 Living eye in book design can open and allow some alien being to see
02 Magical gems with a d4 petty magic abilities
03 Magically sealed and warded with glyphs and runes of magic 
04 Book opens and closes and can attack AC 16 HD4 Att d4 butt MOV4"
05 Book requires blood sacrifice to read the text for a a day at a time
06 Book contains an evil spirit that attracts evil creatures and taints where it is used
07 Thee book is cursed, reading it draws a evil alien entity to fall to earth from the stars, 
08 Book holds spirit of evil wizards ghost which tries to possess reader
09 Reading from it creates a dream link with a ancient elder evil being through dreams
10 A spirit takes a student form and offers to serve the owner as an apprentice or lover
11 Book is of interest to petty gods who come to visit the wielder monthly
12 Every full moon imps and gremlins and other petty evils are attracted
13 Every month planar beings come to judge wielder, will aid or torment them
14 Every night the book is left a poltergeist comes from inside, every month a wraith
15 Book has a picture that is a gateway to a pocket universe complex
16 Book has a picture that is a gateway to a far away land
17 Book has a picture that is a gateway to a another time
18 Book has a picture that is a gateway to an alien plane of existance
19 The book is cursed and may change the readers alignment if they fail to save each use
20 Reading it induces mutations if the reader fails saving throw

d20 Book Magical Defenses
01 The book teleport to safety if threatened by harm
02 If the book is harmed demons are summoned to save it
03 Face on the book is a bound planar being who guards thee book from unworthy
04 Book charms the wielder who fails a save, comes to love the book ahead of own life
05 Book has a bound elemental, demon, devil or deva or otheer planar defender bound to it
06 Book is wizard locked requiring a magic password to open
07 Book has sigils blast any person for thee first time 4d4+4 dam save halves*
08 Book can shoot a magic missile per round if shooting at any in range who threaten it
09 Book resistant to d4 1=fire 2=acid 3=lightning 4=cold, magic or natural or dragon breath 
10 Book releases ghost if attacked of long dead wizard
11 If threatened 20HD of undead are conjured to defend the book
12 If threatened a golem forms from the book cover to defend it
13 A swarm of insects pours from the book to attack any who threaten it
14 Anyone harming the book or stealing it gets a legendary curse lasting generations
15 The book may cast call lightning to defend itself and strike enemies in range
16 Book is intelligent like a magic sword, has an alignment and might dominate wielder
17 Book connects wielder in sleep to the magical nightmare land, a dimension of horrors
18 Protected by influence of d4 1=evil god 2=demon prince 3=duke of hell 4=elemental lord
19 Book contains a trapped petty god who's cult  try to free it or it tries to escape
20 Book turns into a dragon if damaged which attacks then escapes
*nope it can't be used as melee weapon while held by same wielder but perhaps you could throw it at people then risk picking it up again

d10 Quick Worst Book Subtypes
01 Elemental Lore - heretical sects and cults of the elemental planes
02 Necromancy - undead magical lore used by evil necromatic priests and wizards 
03 Demonology - manuals used by cults or cultist wizards to gain power from demons
04 Diabolism - manuals used by cults or cultist wizards to gain power from devils
05 Eldritch Lore - maddening cults of ancient elder evils of the outer darkness
06 Heretical Lore - breakaway sect of a religion branded heretics and mostly killed
07 Esoteric Lore - esoteric epistemology, cosmology, eschatology and planar theory 
08 Occult Theory - magical theory and practices
09 Blasphemous Lore - banned slander against the gods hated by the church
10 Forbidden Lore - secrets of the gods and dawn age kept hidden from humanity for aeons

Format:
Name
Content
Abilities

d100 Worst Books in the World

01 Book of the Living Fire
Details of fire elemental magic and the evil elemental nobility
+1Lv to caster for any fire spells used while holding the book 
02 Book of the Outer Aether
Details of air elemental magic and the evil elemental nobility
+1Lv to caster for any air spells used while holding the book
03 Book of the Pristine Waters 
Details of water elemental magic and the evil elemental nobility
+1Lv to caster for any water spells used while holding the book
04 Book of the Cosmic mountain
Details of earth elemental magic and the evil elemental nobility
+1Lv to caster for any arth spells used while holding the book
05 Tome of Elemental Unitarianism
Ancient cult that tried to unite elementals to conquer the world
+1Lv to caster for any any elemental spells used while holding the book -1 Lv for other spells
06 Manual of Elemental Chaos
Demonic cult tried to dupe victims into elemental worship as a gateway to demon cults
+Lv to on one chosen element, if detecting or protecting from alignment
07 Book of Eternal Winter
Details of ice elemental magic and the evil elemental nobility
+1Lv to caster for any ice or cold spells used while holding the book
08 Book of Violent Storms
Details of lightning elemental magic and the evil elemental nobility
+1Lv to caster for any lightning or storm spells used while holding the book
09 Book of Endless Mists
Details of vapour elemental magic and the evil elemental nobility
+1Lv to caster for any gas or vapour spells used while holding the book
10 Book of Volcanic Destruction
Details of magma elemental magic and the evil elemental nobility
+1Lv to caster for heat or lava spells used while holding the book
11 Book of Eternal Undeath
The secrets of lichdom with several formula to gain immortality and power
Book acts as the soul hiding device to attain lichdom, save or evil wizard takes your body
12 Book of the Dead
A guide to the underworld and secrets of making mummies
Gain an etiquette skill, and underworld lore skill, can contact dead ancestor per week
13 Tome of Osimancy, the Book of Skulls
A guide to necromancy specializing in bones including skeletons and bone golem formula
+1Lv to caster for any bone spells used while holding the book
14 Tome of Carnomancy, the Book of Flesh
A guide to necromancy specializing in flesh including zombies and flesh golem formula
+1Lv to caster for any flesh spells used while holding the book
15 Tome of Sanguinmancy, the Book of Blood
A guide to necromancy specializing in blood including vampire creation formula
+1Lv to caster for any blood spells used while holding the book
16 Tome of Animancy, the Book of the Spirit
A guide to necromancy specializing in breath including invisible stalkers
+1Lv to caster for any animus or mental spells used while holding the book
17 Book of Dank Spirits
Formula for summoning non corporal beings and beings that might offer power or madness
+1Lv to caster for any spirit spells used while holding the book
18 Book of Underworld Wisdom
Guide to using spirits of the dead for information like divination and prophecy
+1Lv to caster for any divination spells used while holding the book
19 Book of Utter Darkness
Secrets of the planes of darkness, secrets of shadows 
+1Lv to caster for any darkness or negative energy spells used while holding the book
20 Demonomicon
Book used by great wizard to contact and dominate demon princes of the abyss
+1Lv to caster for any demon spells used while holding the book
21 The Book of Vile Slime
Secrets of demon nobility of slime, ooze, fungus, disease and chaos
+1Lv to caster for any slime or acid spells used while holding the book
22 The book of Eternal Night
Secrets of demons of darkness, undeath, nightmares and shadows
+1Lv to caster for any darkness or negative energy spells used while holding the book
23 The Book of the Balor
Names and lives of the greatest breed demons and the great chaos jester
Book can summon a Balor Demon up to six times then the user is taken to the abyss
24 The Festering Secrets of the Plague Lords
Becoming a carrier and names of plague demons and their abyssal spawn pits
+1Lv to caster for any disease or swarm spells used while holding the book
25 The Demonomicon, the book of lost names
Book of names of demons of lower ranks and mans to contact some nobility
Book acts as protection from chaotic evil to wielder
26 The Book of a Million Chittering Ones
Rambling self contradictory history of demonkind versus the hierarchies of haven and hell
Book can conjure a random lessr devil with a human sacrifice once per Lvl pr week
27 The Fall of the Evil One
The fall of the beast in it's last few incarnations and warning signs of it's next form
Book can detect anyone with evil alignment on sight and hides the wielders alignment
28 Journeys in the Screaming Abyss
Fragments of tales of planar exploration in the abyssal worlds, fragments left from creation
Can open unstable random chaos wormhole for a d4 rounds per level once per day
29 Strange Cults of the Old Country
Secret document church used to teach demon hunting also popular with cultists too
Detect evil spell at will while holding
30 Demon Haunted Places in the Kingdoms
Tells of old cults and monsters and ruins where demons were seen in the past
Detect magic while holding the book
31 Psychogeography of Hell
Guide to layers, gates and secret ways of hell
Find a hellgate once per week
32 The Diabolicon
Guide to summoning devils to do your bidding, grant wishes and selling souls
+1Lv to caster for any devil spells used while holding the book
33 The Book of Thralls
Guide to regulations of hell, punishments, transmigration's, promotions and demotions
Summon lesser demon or devil once per week serve hour pr Lv 
34 The Book of the Damned
Names of demons enthralled by devils of hell, used as mercenaries and bounty hunters
Summon lesser demon once per week serve hour pr Lv
35 Decent into the Underworld
Many books on adventure of hero or god entering and escaping the underworld
Find entry to underworld once pr month
36 Torments of the Damned
Lists of torments, punishments and horrors of hell
Sacrifice evil person and create a larvae
37 Armaments & Agents of Hell
Explains hellish conspiracy serving Hell including witches, damned pawns and devil cults
Can work bronze or brass metal into +1 weapons or armour or tools with on months work
38 The Great Rulers of hell
Details on the lords of each layers and other major dukes and nobles
Contact lords of Hell through their portraits to make deals with them, one use per person
39 The Devils Outcasts
Devils caught for corruption and banished to wastelands on the first layer of hell
+1Lv to caster for any spells used on an outcaste devil while holding the book
40 The Devil's Legions
Names of legions of hell, their offices and names of their military orders
+1Lv to caster for any spells used on a devil in the infernal army while holding the book
41 The Elder Book
Evil wizards in age of darkness documented how ancient elder gods were banished away
Conceal alignment while held, +1 Lv to all darkness magic
42 Elder Cults
Details over a dozen major cults and mentions many lesser sects of the elder gods
Conjure lesser deamon or demon per week
43 Book of the Old Ones
Spells and summonings used by elder cults, how to locate their their ancient stones
+1 Lv on any spells cast inside a stone circle or by a elder monolith
44 Dark Places in the Earth
Caves, wells and dark places where the forgotten dark gods or their minions dwell
Wielder can see in the dark but monthly saves or gets a petty subterranean mutation
45 Cults of the Sea Folk
Details of elder sea demons, their minions, cultists and dread secrets
+1Lv any spell vs evil water monster
46 Book of the Serpent
Serpent man cult manuals with places to seek serpent men hidden refuges
+1cs any reptilian spells
47 Calling Strange Spirits from the Stars
Cults and rituals of strange star spirits, shunned by normal people
Conjure alien star spirit per week
48 Savage Rites of Backward Peoples
Descriptions of cults of savages met by explores and travellers
Conjure Lsser Elder Damon per week
49 Unseemly Callings From Beyond
Summoning entities and strange abstract beings from beyond space and time
Call forth a invisible stalker per week
50 Servitors of the Outer Gods
Details various alien races and servants of the elder gods
Call forth a gate to an elder god per week, can bargain with alien beings
51 Book of thee Black Sun
Heretics who plot treason against the sun god from within his celestial bureaucracy
+1 Any darkness or negative plan spells
52 Books of the Bloodlords
Details cult of the blood druids who use evil murder magic and make monsters
Can turn sacrifice into a d4HP haling potion once per level per day
53 Hunger of the Woods
Detailing cruel elves, mischievous spirits, hags and woodland horrors of the wilds
+1Lv any plant magics
54 The High Witch Book
Teaches various sects of witchcraft cults, some serving demons or underworld gods
Lets you choose your familiar instead of roll, alerts you when cult recruits in area
55 Calling Strange Spirits
Entities that can be contacted for advice and their prices for knowledge
Wielder of thee book can see invisible spirits and attempt to speak with them
56 Secret Names of Things
Using the creation words for magic and how they were used to crate the cosmos 
Study astrology for a wek and gain +1 Lv vs a single foe by divining their true name
57 Worlds of Shells
Details the fragmented minute worlds left over from the material creation of the universe
Open a gate per week to a different micro world 
58 Secrets of the Book of Life
Using words of power stolen from the gods to create golems and animate matter with life
Can crate a golem HD per month once a lab has been built for each type then a cost in gold and time for each type
59 Secrets of Making Orcs
Spells to make orcs from corpses, elves, humans and even from great mud spawning pits 
Once a week can create an orc per lvl from any humanoid intact corps
60 Secrets of Beastmen
Ritual surgery and drugs used to makes beastmen as used by ancients to make slaves
In a week can make a animal and human into a resentful beast person hybrid in a lab
61 Celestial Cosmography since the Dawn Time
Evolution of the multiverse and structure of the planes
Once a week can create a gate to the dawn age and is hunted by cults
62 The Faerie Roads
Traveling through the world tree, cloud land, elfland, the underworld and the overworld
Find a gate to faerie land once per month
63 Rites of the Monster Kings
Rites to call demons or open gates and where the oldest banished evils hide away
May conjure a demon or open an abyssal gate per week
64 Dance of the Celestial Spheres
How to predict with astrology where gates will open during planar intersections
Call a time elemental once a month and bargain with it for service
65 The Eternal Balance
Details the forces of neutrality between law and chaos who try to protect people from extremes or imbalance
Detect All non Nuetral or balanced alignments (good, evil, lawful or chaotic) while held
66 The Roads of Chaos
Using primal chaos to travel in time, space or through planes through gates
Open a portal to primal chaos per month with a ritual and sacrifice
67 Entreaties with the Lords of Overspace
Dealing with archons and daemons of law and order who have difficulty manifesting
Protection from chaos while being held
68 Lives of the Great Dragons
Details their wars with giants and gods and thee great dragon ancestors and their return
+1Lv to caster for any spells used on any dragon blood being while holding the book
69 Lore of the Worm
Wisdom of the oldest life from the darkness and waters, how to become an immortal worm
+1Lv to caster for any spells related to worms while holding the book
70 Lore of the Insect
Once a great power now they, mostly food but their ancient gods and demons are still great
+1Lv to caster for any spells related to insects while holding the book
71 The Dragon Formula
Alchemy manual to build apparatus and brew up a dragon
Grow a dragon in a 10 000gp lab, 1000gp per Month pr HD to grow a resentful willful monster
72 The Dragon Kings Roads
Locations and secrets of activating gates across the world or to other planes using rituals
Once a month find a teleporter gate within d10 miles
73 Ways of thee Beast Lords
Details ancient spirit cults of barbarians and servant races of the great bast gods
May transform yourself into a beastman over a month in agony
74 The Jade Seal
Famous alchemy work claiming secrets of immortality and linked to a cult of lotus eaters
Can be used to identify a potion as a skilled expert with a INT roll
75 The Philosophers Stone
Secrets of alchemy and making a philosophers stone, with many recipes for potions
Shovel in gold into book to form a lump of alchemical matter able to replace missing ingredients
76 The Enchanters Secrets
Recipes for many magical items, potions and scrolls and cursed items in evil versions
Allows wielder to craft a common magic item per month
77 The Words of Power
Magical theory of creation
Allows wileder to create a scroll per month
78 The Lapis Tablet
Describes demon inspired undersea empire of evil at war with good sea faerie folk
+1 Lv of water magic
79 Exploring the Dreamlands
How to visit the dreamlands, avoid the nightmare powers and rule a demiplane
Conjure Monsters once per Lv per day
80 Astral Lore
Details of the spirit world and entities found and how to deal with spirits with good manners
Astral travel once per month
81 Debasement of the Gods
How gods of evil killed and defiled the good gods for power, how to sacrifice victims for power
Wielder cannot be detected or spied on with magic
82 Crown of the Wizard King
Blasphemous wizard king who destroyed religious cities and cults in his conquests
+1 Lv vs priests or divine magic
83 Secrets of the Lich Lord
Teaches methods of necromancy and allows the creator to contact the reader through dreams
Can call a skeleton chariot 1HD/Lv Mov24" 3d6 Trampl Att once a month for a day
84 Engines of the Dawn Age
Descriptions of great artifacts used by the dawn age peoples and their operation
Detects nearest machine then required components
85 Forgotten Gods
Killed, banished, petty and de powered gods and how to try to exploit their remnants
Meet a petty god per month, perused by cults
86 The Sunken Empire
details of a long lost great power that ruled the world but was flooded
Wielder has free action and breathe water while holding book
87 The Seven Celestial Kingdoms
Details the seven heavens and the surrounding Arcadian fields and wars fought there
Open a gate to Arcadian fields near gates of heaven
88 Hidden Kingdoms of the Underlands
Lore of the underland kingdoms
Open gate from surface to subterranean world or viv versa once pr month
89 Sagas of the Elder Age
Stories of barbarians killing evil wizards and monster kings used to find eldritch locations
Detect Magic if holding book
90 Book of the Eye
Secrets how a master sorcerer can awaken talent in a pupil with drugs, suffering and other ordeals
Contact other plane once per week
91 The Book of Xor
Book of living dripping flesh, part of Xor and able to open a gate to the kingdom of flesh
+1 per dice for any healing magic or summoned creature HD
92 The MonsternomiconDetails the old and final monster kings, their gods, servants and thrall races
+1 per HD of summoned creature HD
93 The Book of Portals
Open planar gateways especially into the dungeon and sewer dimensions where you can reach hell and other planes
Find a entry to the hell's sewers or th dungeon dimension once per month
94 Beyond the Crystal Sphere
Speculations about outsider alien entities from beyond the multiverse
Can find exit from the multiverse once per year
95 The Book of the World Machine
Book of law explaining machinery of the multiverse and how great cogs explain all history
Find a entry to the cosmic plant room once per month where archons work
96 The Book of the Great Tree
Using the cosmic world tree to plane travel via the worlds within the tree according to seasons
Find a entry to the world tree once per month
97 Secrets of Sky and Sea, secrets of the Navigators
Maps of seas, magical locations, means to predict weather and travel by sea or the fairy land sea realm or dreamlands
Always detect the north star and can see the stars, see in the dark under stars
98 Stories of the Damned
Tales of those who sold their souls to hell and what happened to them, a few escaped
Find a exit from hell once per month
99 Hail to the Dungeon Spirit
Makes the the dungeon connect to the great dungeon dimension, a self aware evil dimension
+1Lv to any speell cast in the dungeon
100 Deals with the alien magic and technology of another plane teaching you to use your native powers on Planet Psychon

Can find a gateway once per month from either your home plane or Psychon