From publisher blurb: This book contains the complete core of the Era d10 Rule Set, and is suited to guide players through the mechanics, or as a quick and easy way to reference the core rules. This modular system is easy to use, but complex to master. It offers a set of rules which are tailor-made for each setting that we create. The specifics for each world can be added to or removed from the "Fundamentals" of the rules to create the flavour that's wanted - Sci-Fi, Fantasy, Survival Horror, Modern and so on.