Trivia
On September 28, 1991, The Ninja Warriors was put on the infamous German index by the BPjS. For more information about what this means and to see a list of games sharing the same fate, take a look here: BPjS/BPjM indexed games.
In addition to the usual "infinite lives" cheat modes the game featured a number of strange modes implemented by the programmers during testing while they were waiting for new bug lists. These included.....
Snow white - the Ninja Warriors were displayed minus their torso so that they became dwarves.
Exterminate - the screen changed to a "negative" effect palette similar to the cheapo fx used in Doctor Who when the Daleks were killing people.
Casablanca - black and white display
One small step - moon gravity made all jumps 5 times larger and falling much slower.
Kylie - the music played out of tune
Upside down - the screen was displayed upside down
....etc etc etc. In total there were 16 of these different cheat modes.