Ninja Gaiden III: The Ancient Ship of Doom
Ninja Gaiden III: The Ancient Ship of Doom
18 minutes after the end screen is displayed, if the console is not reset or turned off, the text changes to "TO BE CONTINUED NINJA GAIDEN II". This signals that the game actually takes place between the events of Ninja Gaiden and Ninja Gaiden II.

This message isn't displayed in the American version.
Contributed by Kakariko Kid