The G.G. Shinobi II: The Silent Fury (ザ・GG 忍 II) is a side-scrolling action game by Sega released for the Game Gear in 1992. It is the sequel to The G.G. Shinobi, an off-shoot of the Shinobi series created for Sega's portable platform. The player controls Joe Musashi as he rendezvous with his ninja allies from the previous game, giving the player access to different characters with unique abilities as the game progresses.
Joe Musashi has to rescue the four fellow ninja and retrieve their corresponding Elemental Crystals, before the final showdown against the evil Black Ninja in his castle.
Source: Wikipedia, "Shinobi II: The Silent Fury", available under the CC-BY-SA License.