A Complete Game All in One Book

Old-School Essentials is a modular game where the core rules of the game are extended by additional "rules modules" which add content for different genres of fantastic adventure. The Old-School Essentials Rules Tome is a compilation of the core rules plus four rules modules, forming a complete game for Classic Fantasy

Core Rules for character creation and advancement, adventuring in dungeons, the wilderness, and at sea, magic and combat.
Classic Genre Seven classic classes (cleric, dwarf, elf, fighter, halfling, magic-user, thief), complete lists of weapons and adventuring gear, extensive lists of vehicles, mounts, and vessels, mercenaries and specialists for hire, rules for stronghold construction.
Classic Cleric and Magic-User The complete set of 34 cleric spells (from 1st to 5th level) and 72 magic-user spells (from 1st to 6th level), for use by players or cleric, elf, and magic-user characters.
Classic A selection of over 200 classic monsters to challenge adventurers of all levels.
Classic A hoard of over 150 wondrous magic items.
The material in this book forms a complete clone of the classic Basic/Expert game, including all rules, classes, spells, monsters, and magic items.