This study aimed at developing a Multiplayer Online Role Playing Game-based (MORPG) Learning system which enabled instructors to construct a game scenario and manage sharable and reusable learning content for multiple courses. It used the curriculum of "Introduction to Computer Science" as a study case to assess students' learning effectiveness on the subject of "computer network". The sample was 56 freshman students, who were randomly assigned to two groups, one of which used the game-based learning and the other one the Web-based video lectures. Furthermore, this study also conducted the System Usability Scale (SUS) to measure satisfaction, usability and learnability of the developed management system for instructors. Five instructors were invited to participate in the practical use and evaluation. The results showed that game-based learning could be exploited as effective learning environments and game design system was usable and learnable for instructors to create learning games.