Persuasive games are a subset of serious games that are getting increased attention from the gaming industry as well as researchers. Although their title implies they can be intuitively defined as having the primary intention of changing or reinforcing players' attitudes on certain topics, only a handful of studies have provided evidence that these games actually influence attitudes. After presenting a summary of previous studies' results, the current article expands on this evidence by reporting on a controlled online experiment that compared a currently playable persuasive game (My Cotton Picking Life) to a mobilizing YouTube clip covering the same topic. The study included a pre-and post-test and two media conditions. 237 individuals (mean age of 23) from an international population participated in this study. Since the persuasive game and comparable movie clip were concerned with forced labor in Uzbekistani cotton fields, attitude scales on empowerment, the workload of cotton picking, and denial of the issue, were composed for this study and subsequently validated. Results showed a greater increase on workload attitudes for individuals who played the game than for those who watched the clip. Enjoyment of the game as well as awareness of the game's intent also increased the attitude change from pre-to post-test. The paper offers insight into how persuasive games can be further validated with different methods, and concludes that there is mounting evidence for the viability of games as a medium for persuasive communication.