Mario Maker looks like it could be revealed by Nintendo at E3 next week.
Judging by a snapshot allegedly from the E3 show floor published on Nintendo Enthusiast, Mario maker would allow gamers to create their own custom Super Mario Bros style levels.
The hoarding depicts a stylus-wielding hand, suggesting perhaps a 3DS release, although of course the functionality would presumably work perfectly well on the Wii U GamePad.
Nintendo’s E3 reveal will take place via a special Nintendo Direct video at 5pm on Tuesday June 10th.