Kousoku Card Battle: Card Hero

Kousoku Card Battle: Card Hero is a card battle RPG for the Nintendo DS, sequel to the Japan-only Game Boy Color game Trade & Battle: Card Hero, and was also only ever released in Japan.

Unused English Mode
Apparently, there were some early plans to localize this game for Western markets, as the Japanese release still holds the remnants of an English language mode. Next to the folders with the text for the Japanese kanji and kana modes (jp and kn), there is also a folder called us which contains an assortment of leftover files - some text has been translated into English, some files have Japanese or English placeholder text, yet others are copies of their respective Japanese files, while many files are either empty or outright missing.

This highly incomplete English mode can still be enabled by, for example, changing the folder from which the game loads its text. Offset in the ROM holds the string jp, which as mentioned before is the folder name for the kanji mode text. Changing this to us will make the game use the English text when kanji mode is selected in the game's settings.

Note that, besides the obvious state of incompleteness, the game will crash shortly after beginning the story mode.