The serious games industry needs game engines, or frameworks, that have been developed specifically with this sector in mind. This paper discusses the criteria that such engines need to adhere to in order to support viable solutions. These criteria are illustrated on the basis of SimPort, a novel multiplayer management game framework. SimPort has shown to be very powerful, functional and easy to use in the development of MV2, a game module simulating a major expansion project, the Maasvlakte 2 area, of the Port of Rotterdam in the Netherlands [8]. In addition, from MV2 real-life usage so far, players and tutors have concluded that this game is not only rather educational, but also a lot of fun to play.