Darkest of Days is a first-person shooter from developer 8monkey Labs and publisher Phantom EFX featuring a time-travelling protagonist who must set time streams right using an assortment of both period and futuristic weaponry. Take this demo, for instance. The same one released for the PC back in August, it runs the character through a tutorial mission and then drops them in the middle of the Civil War battle of Antietam with a primitive musket, before letting them cut loose later on with a fully automatic machine gun. It's a beautiful thing.

The demo is available to Gold Xbox Live subscribers right now, with Silver members having to wait until September 22nd to give it a go. For those of you far from your beloved console, you can add the demo to your download queue here.

Three levels were available in the demo that 8monkey had up and running at their PAX booth, which was festooned with period weapons and employees dressed up in historical garb, right up to publisher Phantom EFX's CEO and game designer Aaron Schurman wearing Roman hardened leather armor, complete with plumed helmet.

Schurman gave me a basic overview of the game as I played through the opening level as a member of General Custer's doom band during the Battle of Little Big Horn. Your character is an MIA - missing in action - a person who was unaccounted for at the end of a major battle or disaster. The concept behind the game is that a futuristic time agency warps in and recruits these MIA's to put them to work fixing errors in the time stream. He explained that one of your character's contacts is an MIA from 9/11, a policeman who was off-duty on the day of the tragedy, running to help but managing to (nearly) get killed in the process.

The concept made me a little sad, but Andrew made me look at things another way. "It is sad that they are gone, but it's good to imagine that these MIAs are actually still out there somewhere, making a difference for the rest of us."

Back at the Battle of Little Big Horn, I fired my primitive pistols as hordes of Native Americans swarmed about on horseback and on foot, charging the small hill we were trying to keep. Soon I found myself felled by an arrow, seeing it sticking out of my chest as I struggled to take as many of the enemy down with me as I could. Then a strange bubble appears and a man dressed in futuristic armor beckons me to join him, only to be shot dead as I enter the warp and the level ends. Interesting.

During the swarming of the Indians, I did notice a little bit of slowdown due to the sheer number of enemies on screen at once, but the effect was still rather impressive overall. Another thing I noticed was that the enemy NPCs didn't seem to be all that interested in me, a worry that carried over into the next level.

The second level saw me fighting Germans during World War II, only this time around I had a futuristic shotgun at my disposal. The Germans charged our trenches, and I hopped out, running through the enemy and taking them down in what I can only image was a very surprising way as far as they were concerned. I didn't spend too much time in this level, but again I noticed that the German soldiers didn't seem too concerned with me hanging about.

The third level cast me as a Union soldier during the Battle of Antietam, armed with a primitive musket with a rather long reload time. Luckily Darkest of Days has a quick reload function, with your character getting things done a bit quicker if a button is pressed at the correct time. The first pitched battle I fought was very, very period, with both armies facing off across a ditch, simply standing, firing, and then reloading as quickly as possible in order to fire again. Primitive, but entertaining nonetheless.

Soon our forces were on the move again, and I met up with a fellow time operative who hooked me up with an automatic machine gun. An automatic machine gun during the Battle of Antietam. Lovely.

Butternut-wearing members of the Confederacy fell in great numbers, but 8monkey was careful to make sure that you couldn't simply unload with your future ordinance all willy-nilly. Certain key soldiers are marked as survivors, and you cannot use your future weapons while they are awake and aware. In order to overcome this obstacle, you toss out a handful of these little balls, which will seek out survivors and put them to sleep, allowing you to go to town with your little friend.

Falling to put a survivor to sleep, however, will alert the rival time-travelers who are trying to alter history. Once they realized someone that was supposed to live has died, they get a fix on you and come to investigate. This is not a good thing.

So I played through most of the three levels available, finding Darkest of Days to be a solid little shooter with some great ideas behind it. As I was leaving, Aaron Schurman explained that while the demo gave players a great feel for the gameplay, there's a deep, enthralling story behind the game that the demo just doesn't communicate.

I suppose we'll find out if he's right soon enough. Darkest of Days hits the PC and Xbox 360 tomorrow.

Darkest of Days will have PC and Xbox 360 owners hopping all over time this September, so it makes sense to bone up on some of the historically accurate and futuristically exotic weapons you'll have at your disposal. It's nice to see a musket in a first-person shooter, though that reload time must be a real bitch. I particularly love the bullet point for the shotgun, which pretty much sums up my feelings about shotguns in shooters since time began.

Darkest of Days is a time-travelling first-person shooter, developed by 8monkey Labs and published by Phantom EFX, hitting retail shelves on September 8th. Players step into the muddy boots of Alexander Morris, a foot soldier who transfers into Custer's regiment days before the Battle of Little Big Horn. Right before he bites the big one, tomahawk style, a time agent warps in and takes him to the future. A rogue agency is trying to change history, and it's up to the player to revisit the famous battles of history to set things right. You'll visit World War I and II, the Civil War, and judging by that screenshot, ancient Rome, though your spear is definitely bigger than theirs.

The game features a new proprietary engine known as Marmoset, allowing for hundreds of NPCs on the screen at once, each acting according to advanced AI, and nifty mechanic where key people who cannot be killed no matter what are highlighted in blue, meaning that running and gunning without thinking is out of the question.

Of course, the best feature is the ability to bring a laser rifle to World War II. Screw temporal paradox.

I'm interested to see how Darkest of Days turns out. Time-travelling shooters have the potential to be pretty amazing, but then again...

At the forefront of their four press release rampage is the announcement that Sega has licensed both the PhysX technology and NVIDIA's APEX technology to serve as a development platform across all Sega studios.

"Sega has been using PhysX technology for several years, but this new agreement enables our studios to take advantage of the full portfolio of cross-platform PhysX engines," said Takashi Shoji, Department Manager, Consumer Software R&D Support Dept., Consumer R&D Division, SEGA Corporation. "APEX was an important factor in our decision because it enables us to create high quality physics content in an easier and more productive manner."

Basically taking away a great deal of the workload so Sega's programmers can concentrate on slowly killing Sonic.

Along with the Sega announcement, NVIDIA also revealed that Capcom's Dark Void uses PhysX to render weapons, smoke, and debris; GRIN used it in Terminator Salvation for weapon effects and destructible environments; and 8monkey Labs has an amazing name.

Oh, and 8monkey used PhysX in Darkest of Days to help create interactive, expressive, and natural environments.

In short, NVIDIA's PhysX technology is slowly taking over the world, and the company's public relations team has far too much time on their hands.