Time Commando

Time Commando is an action-adventure computer and video game developed by Adeline Software and published by Electronic Arts in Europe, Activision in America (United States and Brazil), and Virgin Interactive (PlayStation version) and Acclaim Entertainment (Sega Saturn version) in Japan. It was originally released for the PC on July 31, 1996 in Europe, United States and Brazil, and was later ported for PlayStation and released on September, 1996 in Europe, on September, 1996 in the United States and on November 15, 1996 in Japan. A Sega Saturn version of the game was also released in Japan on March 5, 1998.

The game takes place in the near future, and the military, with the help of a private corporation has created a computer capable of simulating any form of combat from any point in history. However, a programmer from a rival corporation infects the system with a virus(in the game introduction scene, is introduced as "Predator Virus") that creates a time-distortion vortex, which threatens to swallow the world if it is not destroyed. The player controls Stanley Opar, a S.A.V.E(Special Action for Virus Elimination) operative at the center who enters the vortex to try and stop the virus. In order to accomplish this, the player must combat various real-life enemies throughout different time periods. These eras include Prehistoric (featuring cavemen, saber tooth tigers, and cave bears), Roman Empire, Feudal Japan, Medieval, Conquistador, Wild West, Modern Wars (World War I and supposedly World War Three), Future, and finally, a showdown with the virus.

Source: Wikipedia, "Time Commando", available under the CC-BY-SA License.