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The Cannonball is an item that appears exclusively in the SNES release of Mario is Missing!. It is a part of the ammunition for the Tsar Cannon (named the "Emperor's Cannon" in-game, which is also depicted in the item's image) that is exhibited in the Kremlin. It is stolen from its proper place by a group of invading Koopa Troopas, and it is then carried around by a single Koopa Troopa wandering through Moscow. Luigi eventually grabs it for himself and asks the city's locals about it, leading them to discuss its history and various facts about it, such as how the cannon's cannonballs were cast in 1586 alongside the cannon (in actuality, they were cast in the 19th century). Luigi eventually gathers enough knowledge to bring it to the Kremlin's information booth and prove that the Cannonball that he is holding is genuine. The booth's clerk accepts the item and gives him $1600 as a reward. In the NES version, the Emperor's Bell is instead stolen from the Kremlin.