A time-traveling FPS that involves new ideas to gaming.
A new engine was added to the game to support up to 250 AI (Artifical Intelligence). This makes you feel that you are at the battlefield, and makes it almost impossiable to run and gun. Graphics are a little outdated, but makes up for Physics. This shows all the smoke a gun shoots, and a few other things, like leaves. All the smokes makes seeing targets hard, but shows the intensity of battle. Models of AI are very similar to the different periods, which sucks when you have two modles make a army of 100. Lighting effects are very good though, and overall make a excellent game for massive battles.
New ideas placed in a FPS is the era of weapons you use in each period. The Civil War mainly uses a muzzle loader, and a repeating rifle. Most people think that FPS games are shoot and dodge, but this takes a new approach. Every shot counts, and having to reload makes you think who is the bigger threat, as not everyone is shooting at you most of the time. It would be boring if there wasn't a "mini game" that lets you reload faster, or jam your weapon.
Other weapons you will use is Bolt Action Rifles, Pistols, Machine Guns, and in some cases, future weapons. Take a auto targeting machine gun, and mow down a entire Union line adds fun to those who just hate Muskets. Or just keep shooting a recoiless shotgun, Rocket laucher, a sniper; computes pressure, temperature, anything that changes the direction of your shot.
The main battles you fight are Tanneburg (WW1), which annihilated a entire Russian Army, and Antietam, the bloodiest single day fight of the Civil War. The Civil War takes you to some fo the bloodiest moments of the battle (Millers Cornfield, Bloody Lane, Dunkers Church) and the retreat of the Russians from Tanneburg. You also stop at a POW (Prisoner of War) Camp in World War 2 (WW2), and the destruction of Pompei in Ancient Roman times, which is the climax of the game.
Since you preserve history, certain people need to survive. To do so, you can shoot them on the leg, or use chasers, which knocks them out. If you do kill them, people from a farther future try to kill you, as they are on a other agenda from you. A tiny ugrades system, which can increase rate of fire, accuarcy, reload time, and clip size makes killing people who are meant to live more important to live.
Other than not being able to replay your missions, and the 8 hours it took to beat, this game should be recommended to people who interest lays in historcal battles.