From the cover:
Class Warfare breaks down Dungeon World characters into component parts and recreates them using a mix of 85 different specialties. Choose three and build a new class. Add one to an existing character. Or make your own specialties, then mix and match. With dozens of new moves, spells, and more, Class Warfare is a giant toolbox geared towards one thing and one thing only: awesome characters for your Dungeon World game!