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• The score display uses Kanji numerals instead of Arabic ones. 〇 = 0, 一 = 1, 二 = 2, 三 = 3, 四 = 4, 五 = 5, 六 = 6, 七 = 7, 八 = 8, 九 = 9.
• When Kagekiyo kills a Stone Lion, it will leave one of four hidden Namco characters behind - the Special Flag from Rally-X, a Hoblin from Libble Rabble, the Galaxian flagship or a Red Car from the aforementioned Rally-X.
• There is a safe way of escaping the underground place that you go to if you fall down a pit - if you have 99 Zeni, walk over to the pool of lava. You will be transported to the stage where the creepy old woman speaks for the second time, and she will say a different message. Also, the first cobweb in the underground place never stops generating Skull Spiders until it is destroyed so this is a good way to get the extra Zeni.
• In order to beat the final boss, Minamoto no Yoritomo, Kagekiyo must have amassed all three sacred items - the Kagami Mirror, the Tsurugi Sword, and the Magatama Jewel, which are displayed in the bottom right corner of the screen.