Ninja Crusaders (忍者クルセイダーズ 龍牙, lit. "Dragon Fang Ninja Crusaders") is a Nintendo Entertainment System game that is in the style of the original Ninja Gaiden trilogy of games for the same system where ninjas have to fight against aliens.

Ninja Gaiden (NINJA 外伝?) is a series of video games by Tecmo featuring the ninja Ryu Hayabusa as its protagonist. The series was originally known as Ninja Ryukenden (忍者龍剣伝, Ninja Ryūkenden?, lit. "Legend of the Ninja Dragon Sword") in Japan. The word "gaiden" in the North American Ninja Gaiden title means "side-story" in Japanese, even though the Ninja Gaiden series is not a spinoff of a previous series. The original arcade version, first two NES games and Game Boy game were released as Shadow Warriors in PAL regions. The series gained popularity on the 8-bit Nintendo Entertainment System (NES) for its tight action-platform gameplay, catchy music and, according to G4's X-Play, for being the first console game to have the story presented in cinematic cutscenes. The 8-bit trilogy was enhanced for the 16-bit Super NES in 1995. Sega also released two Ninja Gaiden games for the Game Gear and Master System, the latter only for PAL regions. A new game, titled Ninja Gaiden, was released in 2004 as a 3D action game on the Xbox, developed by Team Ninja, the makers of Dead or Alive. The Ninja Gaiden franchise is well known for its high degree of difficulty, particularly the original NES version and the Xbox revival.

Ninja Gaiden 3 is an action-adventure video game developed by Team Ninja and published by Tecmo Koei. It is the sequel to Ninja Gaiden II and was released worldwide for the PlayStation 3 and the Xbox 360 in March 2012. An updated version titled Ninja Gaiden 3: Razor's Edge was released later that year, originally published by Nintendo for the Wii U. The game is the first in the modern series to be directed by someone other than Tomonobu Itagaki, the former franchise director. In his place is Yosuke Hayashi, the director of the Sigma ports.

Ninja Kid, known in Japan as GeGeGe no Kitaro - Youkai Dai Makyou (ゲゲゲの鬼太郎 妖怪大魔境?), is an NES game developed by TOSE and published by Bandai. The Japanese version was based on the manga series GeGeGe no Kitaro, but the game was changed to the generic "Ninja Kid" and all reference to Kitaro were removed for the American version. This game was followed by a sequel titled Gegege no Kitarou 2: Youkai Gundan no Chousen, which was released the following year only in Japan also by Bandai; however, this game was a role-playing video game and its plot is unrelated to the original.