Diamond City Castle

Diamond City Castle, in the WarioWare series, is a recurring a 16th century Japanese castle, located in Diamond City. Its owner and only known resident is a prince or princess in Japanese attire named after the player, who sponsors Kat and Ana.

In WarioWare, Inc.: Mega Microgame$!, an evil skeleton spirit named Boneheads appears over the Castle's roof at night and takes possession of its sleeping owner. Ana and her crew of ninjas fail at defeating the spirit, and so Boneheads capture her. He gains full control of the royal person and the sky turned red. However, Ana previously manages to send a letter to her sister Kat with Don the Sparrow's help. When Kat receives the message, she and Paw the Dog make their way to the castle and reach the roof, where Boneheads wait for them. With the help of Paw, who turns into a big sword, Kat manages to cut the evil spirit up. The sky becomes blue again and peace returns to the castle.

The castle is also briefly seen in the map of Diamond City in WarioWare, Inc.: Mega Party Game$!.

In WarioWare: Smooth Moves, the castle is called Diamond Dojo. It figures in Kat and Ana's scenario, "Evil Attacks Diamond Dojo," in which it is attacked by the Elephant Ogre. Kat and Ana shows up to fight the monster, but in the end it turns out that it is actually just looking for its son, Little Ogre.

The Diamond City Castle reappears in WarioWare Gold as a setting for Kat and Ana's story in the Touch League. Ms. Munchly hosts the Gourmet Master test, while Ninja Steve handles the Department of Ninja Licensing. At the start of their story, Kat and Ana arrive at the temple to receive their ninja licenses. Believing that Ms. Munchly is in charge of the Department of Ninja Licensing, they sign up for her class, where they must indulge in food to receive licenses. After this is accomplished, however, Ms. Munchly gives them Gourmet Master licenses, revealing that the true test is up ahead. Ninja Steve appears and reveals that he was in the bathroom, and that his class will be starting soon. Kat and Ana then head to the class, feeling overstuffed.

In the game's end credits, Diamond City Castle appears behind an image of Kat and Ana.