Leonel entered a state of unprecedented focus, his mind reaching a state of tranquility as he began to focus on what would most help to achieve his goal: the magic system of this world.
The books were far more complex than Leonel had originally given them credit for. While they didn't store their information in pendants, the pages of their books held a special magical ability to hide and store more information than their dimensions would seem to allow. For the more complex books, it wasn't surprising to get several normal books' worth of information on just a single page or two.
Regardless, the introduction of this world's magic system was fairly simple, or overly complex depending on how you looked at it.