Life Force (Salamader) was a Konami arcade scrolling game released in in 1986 (it was a sequel to a game called Gradius). Some of you may know of a similar game called Salamander. The game included both horizontal and vertical scrolling stages, and two players could play simultaneously. In Salamander, there were two ships the players could control: Vic Viper or Lord British. Those who played Life Force will remember that the premise was to pilot your ship through a human body and destroy viruses and germs along the way.
There were a number of power-ups that players could get in both games, such as better lasers, missiles, and a force field. In Salamander, stage bosses included Brain Golem, which looked like a brain with arms, Tetran, a robotic octopus, Intruder, a fire breathing dragon, Giga, a skull with crazy eyes that spits at you, Tutanhaman attack, an Egyptian death mask, and Zelos, a red sphere with a snake around it. Life Force bosses were similar. This game was released for the NES and then later for the Sega Saturn and PlayStation.