From the introduction: This rules set is designed for old-school D&D-like games. It is broadly compatible with most published OSR products, but the main goal is to create a system that is: Intuitive for new players Adaptable and hackable Compact ... This game assumes you know what an RPG is, what dice are, and the basics of OSR games. Rather than and complete system, this hack is designed to allow experienced GMs to rapidly run games for new or experienced players. In short, there are bits missing. Read another, much more complete OSR system first, and then fill in the missing bits as needed.