A Mario level creator called Mario Maker was announced at Nintendo's E3 2014 Press Conference. This allows users to create and play a level of Mario on the fly.
This game was expected to come out as leaked images of the Nintendo E3 booth appeared on the internet last week. This seems like it will give users endless Mario gameplay. Users will most likely be able to post and share created levels and download and play others.
This game will be released in 2015.
[youtube http://www.youtube.com/watch?v=NLS458ekSEI&w=560&h=315]
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