Legend of the Mystical Ninja

Alternate costumes:
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Collect all 30 Elephant Statues to unlock new costumes for all four characters.


Mystical Ninja History Lessons:
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Also, have the Game Boy Advance game Kessakusen! Ganbare Goemon 1+2 inserted.
At select locations throughout the game, various characters from the Game Boy
Advance game will appear and tell you things about Goemon's past.


Space-Manbo mini-game:
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Have the Game Boy Advance game Kessakusen! Ganbare Goemon 1+2 inserted. At 
the mini game menu, Space-Manbo will now be unlocked. 


Goemon New Age Shutsudou! reference:
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In the second town's underground prison, New Aged Goemon can be found occupying
the second jail cell for his "crimes against the Goemon franchise".