Original sentence: sometimes used interchangeably with the term  is the martial art, strategy, and Special Forces tactics of direct action, espionage, reconnaissance, assassination, unconventional warfare and guerrilla warfare practiced by the Ninja (also referred to in Japan as shinobi)
Edited sentence: sometimes used interchangeably with the term  is the martial art, strategy, and tactics of unconventional warfare and guerrilla warfare as well as the art of espionage purportedly practiced by the shinobi (commonly known outside of Japan as ninja)