Book of Tzakarath (3.5e Equipment)
From D&D Wiki
 The Book of Tzakarath
The Book of Tzakarath is the grimoire of the deity himself, which he always keeps on his person, such that the only way to take it is to kill him. It appears as a black leather-bound book with an eldritch sign on it, and all its pages are blank. It has an effect to entrapture people it chooses (DC 25 Will check, if failed is compelled to read the book), and those that read it enraptured quickly discover that the book is so powerful that it can bestow the ability to cast spells on those that cannot normally do it, but each spell comes at a price.
Spells can be cast from The Book of Tzakarath as if it was a scroll, even if the wielder of the book is not normally able to cast spells. The book is not used up, and the spells can be cast at will, as if they were cast by a a level 9 caster. The book counts as an intelligent magic item. It has an Intelligence score of 50, a Wisdom score of 40 and a Charisma score of 45.
They start with petty, minor cantrips, but progress to great and powerful Epic Spells (DM's choice), as the Caster's morality descends into depravity.
The spells contained within the Book are counted as evil, regardless of whether the original spell was counted as good. It keeps all other descriptors. The Book of Tzakarath cannot be damaged by fire, acid, cold, electricity or sonic. It can only be destroyed by throwing it into the molten core of the world itself.
The book is actually a trap, as with each spell cast the caster's alignment is shifted towards a form of Evil (DC 35 Will check+1 for every spell cast every day, if failed the caster becomes a corresponding form of Evil (Lawful, Neutral, Chaotic)), and eventually vanishes entirely, their fate unknown to the world.