While the mainline Final Fantasy games are already renowned for being some of the most challenging RPGs that money can buy, the series also has its fair share of difficult spin-offs too. Considering these games still fall under the Final Fantasy umbrella, they do contain a lot of the series' most important motifs, such as the deep characters and unique settings, but they also have a chance to experiment with the core gameplay a little bit without running the risk of potentially irritating longtime fans of the series.