During my senior year of undergrad, as a part of a four person team consisting of a programmer and three artists, I prototyped a deck-building card game about electricity production and carbon emissions. The goal of the game is to produce and sell energy to upgrade infrastructure and eventually reach a threshold of wealth before the other players, all while dealing with, or not, the pollution that results from producing the energy in the first place.
The game was iterated upon over the course of multiple playtests. Initially, the game experimented with the idea of the game not being fun to play to support the lesson that polluting the planet for a profit is a bad thing. In practice, we found that if the game is not any fun, no one will play it and thus the lesson won’t even have a chance to be learnt. Changes were made to make the game tolerable, while still attempting to make the players struggle with how their play was affecting the simulated environment.