Video games are pure product risk. What sort of question could you ask to validate your game idea? “Do you like having fun? Would you like to have even more fun?” Practically 100% of the risk is in the product and almost none is in the customer. You know people buy games. If yours is good and you can find a way to make them notice it, they’ll buy it. You don’t need to rediscover people’s desire to play video games.