Well OBVIOUSLY they ripped off Ashida Kim`s real life exploits (like all those other movies, Batman Begins etc) when serving like an undercover Ninja operative in the Carribean. What do you mean Ashida kim wasn`t born back in the 1500`s? Didn`t you play Last Ninja 2 and 3 "Real haterd is timeless!" ? Ninjas can easily travel trough time.