Here's the basic gist of it. The book is broken up into a set of challenges for each map. Certain challenges have rewards. 3 of the challenges are for the Momentum Helm (1 challenge per helm, class specific). 1 challenge for the gauntlets (can be worn on every class, but you only get 1 piece and would need to be transferred). 1 challenge for the chest piece (can be worn on every class, same as above). 1 challenge for the boots (can be worn on every class, same as above). 1 challenge for the shader. 1 challenge for the sparrow. The book keeps track of all progress account wide. You can do everything with one character and unlock everything in the book. ...or you can do the bounties with each character to rank up your event standing to earn toolkits and the chance for 320 helms & class items. Hope that helps