Coming from a GamesMaster interview with Nintendo's Hideki Konno and Kosuke Yabuki...
Blue Shells provide a certain level of tension that helps maintain the excitement right up until the very end of a race. Of course we pay particular attention to balance. Through literally thousands of races, we’ve made numerous adjustments to get it just right. In our opinion, the items in Mario Kart 8 are the most balanced in the history of the series.
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