Ninja (2009) - This film is directed by Isaac Florentine and stars Scott Adkins as a martial artist who becomes embroiled in a battle to protect a powerful ancient artifact. The movie is known for its intense martial arts action and Adkins' impressive fighting skills.
Ninja II (1984) - This is a sequel to the 1981 film "Enter the Ninja. Directed by Allen Holzman, the film features a mix of martial arts action and supernatural elements. It follows a female FBI agent who must combat a ninja that possesses supernatural abilities.
Shaolin Challenge Ninja - It seems you might be referring to 'Shaolin Challenge', a 1985 film directed by Joseph Kuo. Also known as "Challenge of the Ninja," it stars the legendary kung fu actor, Hsu Sheng, and involves a mix of kung fu and ninja themes.
Death of the Ninja - This title might be a bit ambiguous, as it could refer to various films or might not be as well-known.