sourcebook

source +‎ book

sourcebook (plural sourcebooks)

1. A book consisting of a collection of writings on a particular subject.
2. (video games) A publication intended to supplement the core materials of a roleplaying game.
   • 2008, James Wyatt, Bill Slavicsek, Richard Baker, Dungeon Master 4th Edition For Dummies, page 156:

     That sourcebook is aimed at players of fighters, rogues, rangers, and warlords, and by design you're not going to find much in that book to appeal to other characters.

• coursebook