Walmart offers the K'NEX Mario Kart Wii Mario vs. Goombas Track Set for $13.19. Opt for free in-store pickup to dodge the $4.97 shipping fee. That's $2 below our mention from two weeks ago and the lowest total price we've seen. (It's currently $5 under the lowest total price we could find for a shipped set.) It features 119 plastic pieces and requires two AAA batteries (not included).