Alessandro, maybe you miss the story about Teenage Mutant Ninja Turtles?The spectrum is a UK computer and in that time period the word 'ninja' was not allowed.
So can the game's authors please rename it to Hero Gaiden and change the title screen also...for decency's sake.
Really? What about Ninja, Ninja Warriors, Dragon Ninja, Last Ninja II, Ninja Massacre, Ninja Scooter Simulator, Ninja Hamster etc. then?
Yes, they were renamed to Hero Turtles in UK. Some guys decided that ninja is a bad guy, a stealth assasin (which is mostly true) so positive characters in a movie for children can't be called ninja.
But it was just a case with these turtles, it wasn't generally forbidden to use the word "ninja"