McDonald's is launching a very Willy Wonka–esque competition in Japan this month. If you win, you won't get to travel to a world of pure imagination where soda flows in streams, french fries grow on trees, and Big Mac–flavoured bubblegum turns you into a cheeseburger—but you will strike gold.McDonald's Japanese campaign to push two new dipping sauces ("Creamy Cheddar Cheese" and "Fruits Curry Sauce") will end with one lucky winner taking home a real, solid gold McNugget.All it takes is keeping an eye on Twitter and possibly racing around Japan to follow clues leading to the campaign mascot: a masked nugget thief called Kaito Nuggets.In a press release, McDonald's Japan says that Kaito "may appear in some of McDonald's restaurants through the country, may throw out a ceremonial first pitch for a professional baseball game, or pay a visit to a prefectural governor making a surprising request entertaining people."The 1.8-ounce golden nugget is valued around €1,000, and will be given away inside a typical five-piece pack of nuggets. What you're supposed to do with the gold nugget is unclear, but you could always just hock it to fund a trip to that dope Burger King sauna in Helsinki.The contest lasts from June 8 until the 28th. Along with the grand prize winner, 21 runners-up will receive a free, run-of-the-mill five-piece nugget meal with McDonald's Japan's super eccentric new sauces, which is a lot less exciting than a hunk of gold.