This document summarizes a game prototyping workshop presented by Vasilis Gkogkidis and Pete Jenkins. The workshop covers rules and win states, game mechanics, prototyping games, and playtesting. It includes examples of rules and mechanics for games like football and Monopoly. Attendees will participate in exercises to design rules, mechanics, and prototypes for games, then playtest each other's work to provide feedback on improvements. The goal is to help others learn how to effectively design game mechanics and prototypes.