Dragon Quest XI seems to be longer than we think. The game according to director Takeshi Uchikawa the game will take more than 50 hours to complete. That is for the main quest. Including side quest for those who just have to get everything we are looking at a good 100 hours. Not sure how that stakes up to past games but it sounds like you will have plenty to do.
Article:http://gematsu.com/2017/06/dragon-quest-xi-50-hours-long-possibly-100-hours-completionists
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