From publisher blurb:
Why shouldn’t you be able to play a drow or a minotaur in a 1st-level campaign? Why do we need Level Adjustments, racial Hit Dice and Effective Character Levels when we have the most basic mechanics that can work everything out: classes and levels?
The Completist’s Guide to Humanoid Characters presents rules for racial class levels, which allow you to play any humanoid (and a few non-humanoids) at any level of the game, without worrying about Level Adjustments or other complications. Each race has its own progression, with each level granting hit points and skill points, attack bonuses and save bonuses, and abilities unique to the race.
Also included are 13 new crossbreed races, allowing you to play everything from a half-dwarf or half-gnome to a darkheart (elf/orc) or elfling (elf/halfling). Each of these new races also has its own level progression, giving advanced characters more racial abilities.