From publisher blurb:
The Nameless Grimoire is a supplement for The Nightmares Underneath (and other old school fantasy role-playing games) that covers spells and spellcasters.
This book includes:
666 spells and dozens of variations, arranged in 33 spell schools (with simple guidelines for specialist caster), as well as a single d1000 table.
6 new character types: Battle Wizard, Blood Caster, Chaos Mage, Shadowsneak, Sorcerer, and Spellslinger.
Options for supernatural heritage or sorcerous backgrounds that give your characters mechanical benefits and drawbacks.
A new random equipment table for wizards and spellcasting characters.
Random spell name tables and random wizard name tables.
4 other character types: Avatar, Druid, Mystic, and Witch.
Rules for divine patrons and six example patrons.
Rules for crafting your own magical items, made from magical ingredients.
A short bestiary of monsters mentioned in the spells.
The Nameless Grimoire is intended primarily for use with The Nightmares underneath, but you can use it with other old school games if you like. Only the first edition reprints the spellcasting rules, however, and they are not the same as those in the second edition.