Chase Mii (lost Wii U tech demo; 2011)
From The Lost Media Wiki
Chase Mii is a tech demo for the Nintendo Wii U shown at E3 2011. In the demo, a Mii dressed as Mario runs ahead of up to four players controlling Miis in a maze. The players must catch the Mario Mii, and whichever player accomplishes this wins.
In the 2012 Wii U launch title Nintendo Land, there is a minigame called "Mario Chase" that is basically identical to this tech demo, only more refined. However, the original tech demo has never resurfaced.