From the introduction:
Eä Role-playing Game System Advanced Rules (Eä RPGS-AR), is the “advanced” rules system. This is for those gamers who really like a high level of detail in their RPG systems. This has a more detailed character development and combat system, more detail on magic, healing, and nearly every mechanical aspect of the system is more involved, adding more dice rolls, chart look-ups, etc. This is certainly not for everyone, but there are definitely those gamers out there who love getting into the nitty-gritty of a detailed system, and for those who like the extra detail and complexity, this system variant is for you. Of course, those playing the standard system are welcomed, and many may do so, to adopt portions of the advanced system into the standard rules to tweak the portions they prefer to enhance.
The Eä RPGS Advanced Rules Player Manual is intended to offer complete flexibility in character creation and campaign management. The Advanced Rules align quite well with the Standard Rules, while offering less restrictions and greater options.
N.B. large sections of the Advanced Rules manual are incomplete.