Of all of the aspects of game development, Game Design is a long, complicated process that can only be solved via trial and error. Although Game Design can be understood with simple rulesets that define basic game mechanics, it can become a complex problem when many different rules get involved. Moreover, coming up with innovations in this field can be a daunting creative task. Other fields of game development like content creation and procedural generation have created automated tools to facilitate process, but this has not yet been materialized for basic Game Design and prototyping. MaruGen (Machinations Ruleset Generator) is a procedural L-System based tool that aims to fill this gap by creating complex rule-sets from a formal grammar, based on proved simple ones, in an attempt to automate design and encourage innovation via the emergent nature of the rulesets themselves.