As someone who's spent hundreds of hours into Civilization V, which I'll never get back, nor would I want to: I came into this franchise and into strategy games with Civilization V, so it holds an important place in my expanding, exploiting, exploring heart.
I waited for Civilization VI with utter trepidation; spending dozens of hours on the preview build alone, and while I've only played about 50 hours of Civilization VI, here is what I think about Civilization V vs Civilization VI.
In Civilization VI, each city is responsible for its own happiness. Luxury resources provide 4 Amenities which are automatically allocated to your cities in most need. Extra luxury resources may be traded away for new luxury resources plus Amenities, or you can use policies, wonders, Great People or Districts to make up for the difference.
I really enjoy the game and i am very thankful to UkinGame to introduce such a nice game.
