The core rule book presents all system rules needed for play. The book is not organized particularly well, however, and there is little-to-no support for unexperienced players. The central mechanic involves a single D6 roll, attempting to "roll under" a target number which, typically, is a Skill rating. A roll of 1 is always success--and possibly good success, at that. A roll of 6 indicates "something really bad may have just occurred". Both 1 and 6 rolls require a second roll to "confirm", which occurs on a second roll of 1 or 6.