This product line went out of print a while ago, but the fine folks at Alea Publishing Group have been kind enough to reintroduce them. (Thanks for that, by the way!)
Anyway, the character theme (formerly subclass) is a fascinating extra piece of character development based off of multiclassing XP penalties. In this case, it gives some paladin-like abilities to a faithful character to use to represent their religion in battle. It's a neat idea, and it's executed well. In fact, as Alea finished re-releasing the line, I'm planning to base a PC group around the use of subclasses.
[5 of 5 Stars!]