The Solar System is a roleplaying game rules set for heroic tales and fantastic drama. It's strengths are in growth stories with developing player characters who ultimately end up with the power to make world-shaking choices of their own. Players independently choose the Keys that provide their characters with experience, making for a fun and flexible system where gathering experience points actually drives the story and develops character in more ways than just statistically. The system is basically the same as presented in the popular fantasy adventure rpg Shadow of Yesterday, except for some minor updates, clarifications and a rewrite to make it usable in a wide variety of genres. Most of the new material concerns itself with advice and methods for fitting the rules-set into your preferred genre on your own.