The Book of 99 base game is fairly intuitive. You play on a 5x3 grid with 10 ways to win. Getting between 3 and 5 symbols on the payline, in subsequent reels, grants a prize. The book symbol doesn’t pay, but it affects the gameplay massively as it is both Wild and Scatter in one.
The pay table works like this:
Book: Scatter, Wild;
Hero: x500, x100, x10, x1;
Oracle: x200, x40, x4, x0.5;
Cyclops: x75, x10, x3, x0.5;
Witch: x75, x10, x3, x0.5;
A: x15, x4, x0.5;
K: x15, x4, x0.5;
Q: x10, x2.5, x0.5;
J: x10, x2.5, x0.5;
10: x10, x2.5, x0.5.