If you have any questions left prior to the launch of Final Fantasy XV next week, this trailer likely has the answer. You'll learn everything there is to know about the game from character backgrounds and their abilities, gameplay mechanics, and what exactly is going on in the game!
I wasn't too worried about knowing all the details before playing, but I have seen readers comment that they were frustrated as it seemed nothing about the game would make sense unless you saw Final Fantasy Kingsglaive. I don't think that's necessary anymore after seeing this trailer what about you?
