Super Mario Run Now Allows You To Play "One Stage For Free Each Day"

A special event in tandem with the Super Mario Bros. Movie.
Update :
Nintendo of America has now publicised this same Super Mario Run event on its own social channels. This “special event” is being promoted in tandem with the upcoming release of The Super Mario Bros. Movie. As part of this, the game is also half-price until 30th May. A follow-up tweet further explains the free stage unlocks:
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