A vendor that sells a book. What's in the book? Grimoire cards. You can purchase the book, then as grimoire cards are earned you have to pick them up like a package. Each card earned gives rep, and the rep goes towards reward packages, similar to what we have now. The book will be viewable when in that public space at say the vendor or a terminal. You can page through this book to read the grimoire. And Bungie will be adding short playable cut scenes to go along with some cards. There will also be a sharing option so you and your friends (fireteam) can explore grimoire togther, and compare cards.