On Find Mii/StreetPass Quest, during the Secret Quest, there is a gold key that unlocks a path in the bottom right part of the map. The key is acquired by beating the final enemy in the game, Dark Emperor, with a certain condition, but there are conflicting versions as to what this condition is.
A map in GameFAQs states that you need to finish the final enemy with "25 Miis or less", this thread, however, states that people beat it with 22 Miis and didn't get the key.
So, what is the criteria?
Best Answer
A quote from Dark Toshi from Gamefaqs who has a method of consistently acquiring the golden key