To win the nugget, The Huffington Post reported participants have to help find out who is behind Kaito Nuggets' mask and post where he's found with the hashtag #怪盗ナゲッツ, which translates to "Kaito Nuggets," according to an emailed release.
USA Today reported that "Kaito Nuggets appears in some McDonald's restaurants throughout Japan to hunt the ... great-tasting sauces … or he will throw out a ceremonial first pitch in a professional baseball game," according to McDonald's Japan's statement. "He will appear every here and there."
Those "great-tasting sauces," which the contest also promotes, are a creamy cheddar cheese sauce and fruits curry sauce.
Only one person will win the golden nugget, but 21 people will win a coupon for free five-piece nuggets.