Plenty of critics have decried the flood of World War II games at one point or another. Even the more popular scenarios, whether squad based 3rd person titles or 1st person shooters, have started to lose their luster. Hell, just how many Nazis can a gamer shoot, blow up or stab before the entire genre becomes stale, unimaginative or completely unoriginal? Actually, it took the combination of squad based elements and first person shooting to innovate the war game with last year's award winning Call of Duty. The visceral, movie-like play had players begging for more, and, less than a year later, Activision and Grey Matter deliver the first expansion pack for the series, Call of Duty: United Offensive.

One of the more interesting facets of gameplay within Call of Duty is that there actually isn’t a “storyline,” like most other titles. As most CoD vets well know, the game is essentially splintered into separate campaigns or vignettes that focus upon the American, British and Russian campaigns during World War II. (For those of you who don’t, get to a store, buy the original and play it now, soldier!) None of the stories will intersect with each other – in fact, they’re in radically different places from 1941-1945 -- so each campaign comes across like a separate short film or mini-series from the point of view of three voiceless, faceless soldiers.

The American missions are experienced through the eyes of Corporal Riley, a member of the 101st Airborne that’s been deployed to the Bastogne region to flank and distract German troops from their positions. History buffs, or those of you who saw Spielberg’s humbling and visually striking Band of Brothers series might recognize this territory as the Battle of the Bulge and its surrounding push into Belgium. This is a battle that anyone, particularly American citizens, should be respectful of. This was one of the worst battles of the entire war and it was held during the coldest recorded winter of the war. Even worse, many of the soldiers or platoons deployed in the Ardennes forest were cut off from any supply lines or reinforcements during the 40 day conflict, with Nazi forces continually probing their perimeter for weaknesses. That’s right, no food, no ammo and no medical supplies in an environment that could kill you within 30 minutes by temperature alone. While I won’t fully go into the details, let me simply say that if you ever meet a WWII vet, especially one that survived that hellish experience, you’d better give them some respect. That’s the epitome of tough…

Similar to the first Call of Duty, there are a number of smaller skirmishes that often surround a larger conflict. At first, you’ll start with a quick hit and run tactic in the freezing woods of Bastogne, sprinting away from encroaching German divisions and reinforcing your squad’s positions. This leads to actually repelling waves of enemy soldiers and tanks that roll out of the forest towards you. These attacks are much thicker than the first game, and you’ll often see ten or more soldiers sprint towards you with guns drawn. Your semi-automatic weapon simply won’t handle the volume of enemies. Thankfully, soldiers can use the newly included .30 caliber deployable machine guns to mow down these troops where they stand. While they can’t be used when you’re standing or running, once they’ve been set in place, they can cut a wide swath across a battlefield with the high rate of fire.

Historically, once the troops managed to survive the Ardennes forest, it was on to the cities of Foy and Noville. Here, they faced intense close quarters combat from house to house with dug in opponents, often running from building to building to avoid incoming sniper fire. For instance, the hayfields outside of Foy are one of these killing zones where a number of troops were felled simply because they weren’t fast enough to reach cover and avoid bullets. United Offensive introduces a sprint feature simply for maps like this one, where your speed is the difference between staying alive and catching a bullet between the eyes. Not only will you have to fight your way through numerous homes, but you’ll also have to assault farmhouses, barns and even churches as you secure a defensive handhold and prepare for the incoming counterattack. Potentially the most significant example is the Chateau level, where you’re forced to defend a chateau against a number of tanks, half-tracks and scores of troops. Aside from dodging incoming shells and sniper fire, you’ll have to keep your eyes out for rushing soldiers. One tactic that you can use to delay these rushes is to “cook off” your grenades. That means you can pull the pin, hold the explosive for a few seconds and then hurl it at a target, watching it shortly explode after contact. This significantly reduces the chance that the enemy will throw the grenade back at you, and can also be used to clear rooms or corridors of opponents.

While the American campaign is designed to be much more of a continual struggle for ground, with constant attacks and counterattacks at the center of every mission, the British campaign is structured more around stealth than fully direct action. Players take on the role of Lance Corporal Doyle, a crewman in the RAF stationed to one of the Flying Fortresses tasked with bombing Rotterdam. Doyle doesn’t get positioned to the most dangerous spot in the plane (the ball turret, which sustained the most casualties of any bombing aircraft during the war); instead, he’s initially assigned to the dorsal turret behind the cockpit. This turret can swivel in a full circle, which is necessary to repel all incoming fighters – believe me, there will be plenty of them. In fact, as soon as you cross the border into the Netherlands, you run into a curtain of flak and a few squadrons of fighters. As more and more bullets rake your plane, you’re forced to put out fires, operate parts of the plane, and take over for crewmen that are shot in the tail gunner position, amongst other things.

However, your flight seems to be doomed from the start, and thus begins your secondary role, that of a SOE operative. Doyle, thanks to his training, hooks up with a squad of SAS operatives to infiltrate and destroy a number of prime targets that are essential for German troops in their respective areas. This involves things like planting demolition charges on train overpasses or within lighthouses, as well as eliminating hardware like cannons. Thanks to the silenced British machine guns, Doyle and his compatriots can quietly take out a number of soldiers without being detected, but once alarms sound, a speedy chase often ensues, many of which take place on vehicles such as motorcycles or gunboats.

The Russians, unlike both the Americans and the British, neither defend positions nor use stealth as overall tactics. Instead, they have much more of a swarm mentality, attempting to overrun positions with sheer numbers and outlast sieges with bulk manpower. Unlike the first CoD game, United Offensive starts the player (a young soldier known as Yuri) off with a rifle and ammunition. However, the ammunition provided isn’t fully enough to repel the swarms of soldiers and tanks rolling towards the trenches that the Russians have dug. For instance, it’s not uncommon to come across German troops in the trenches burning defenders out of their positions with flamethrowers. Because of the inadequate tactical positions and scarce equipment, Yuri and the soldiers are often forced to run out into the middle of the battlefield to accomplish tasks, such as destroying tanks or taking over buildings.

Considering that most of the time players have to quickly make their way towards a specific area of the map, you can expect some casualties to be high. Often this winds up placing you and your squadmates in a situation where you have to outlast a period of time before more reinforcements can approach your position and support your forces. It’s also quite common to be sent ahead to help clear out potential machine gun nests or snipers, with a host of fellow soldiers waiting in tow to advance as soon as the coast is clear. A massive threat to your comrades that you’ll have to clear is a lot of armor, like tanks or artillery batteries. Fortunately, you can use a pair of binoculars, another new piece of equipment found within United Offensive, to call artillery strikes on a position and eliminate targets.

If you hadn’t noticed before, vehicles play a much larger role in United Offensive than they did in the first game. Tanks, motorcycles, Jeeps, boats and planes have now taken their place within the single player game, and when you’re in the gunner’s seat, all of them require a steady eye and some patience to effectively hit the mark. Controlling these transports aside, you’ll notice a greater number of mechanized hardware in the midst of battle. You’ll often have to take out six or more opposing tanks in some levels while protecting your own, and you’ll often find yourself taking cover from sniper’s bullets behind the thick hide of a friendly machine.

While these machines can sometimes be your worst enemy in single player campaigns, they can become your best friend in Multiplayer matches, which now include medium and heavy tanks, as well as jeeps. Jeeps can carry up to three players, making them fast troop transports with plenty of firepower. Medium tanks can hold only a passenger for a side gunner, while heavy tank drivers have the duty of firing and maneuvering the machine all their own.

There are a number of other tweaks to multiplayer within United Offensive as well. First of all, players have access to satchel charges and smoke grenades for detonations and masking attacks. What’s more, they have the possibility of receiving battlefield promotions based on their play, which rewards them with things such as extra grenades and ammo and the ability to call in artillery strikes. Most of these abilities will come in handy in the three new multiplayer modes: Base Assault is a team-based mode where each side has to locate three bases and destroy their perimeter defenses with heavy weapons such as tank shells or bazookas. Once the defenses have been breached, players have to plant and detonate charges inside the base, effectively eliminating that base as a spawn point in the map. Domination is a mode where teams attempt to claim 5-7 zones on a map by holding the specific area for a certain amount of time. Once that period has passed, a flag is raised and the team can claim points and the territory. The first team to capture every zone wins. Finally, the standard multiplayer Capture the Flag mode has been included, so players can attempt to reach a specific point limit or capture more flags before time runs out to win the game.

If you've played the first Call of Duty, you'll notice that most of the graphics haven't really changed significantly from there to United Offensive. That's not entirely a bad thing, considering that the graphical presentation in the first title helped propel the game to a Game of the Year award. To that end, you'll still notice many of the animated touches that imparts the sense of battlefield chaos raging around you – NPCs will still get blown up around you, enemy machine gun nests rain bullets upon your position, and reinforcements will still scurry out of trucks and other vehicles to support positions. This established baseline of graphical quality means that the programmers could enhance other facets of the presentation, such as a greater emphasis on cinematic presentation. Specifically, at the end of every campaign a movie is generated using in-game footage from the preceding missions, and it's presented like a trailer or TV promo for a movie. It's incredibly satisfying to make it through a tough battle and see specific highlights from the conflict shown in a different way; it actually makes you appreciate the gameplay more.

Many of the particle effects and explosions found within the game seem to have been augmented from the first title. In general, detonations from shells and grenades are much larger, and create much more smoke and debris from impact. It's now possible to lose targets behind the clouds of dirt and smoke generated from large impacts, a tactic that the computer often uses to great effect in the field. This can also be used within multiplayer along with the smoke grenades to mask incoming attacks or snipe enemies with relative safety. Also, pay close attention to the flamethrower effects, which look particularly nasty. However, with the good does come the bad. The German Army apparently underwent Raelian conscription, because every soldier has the same facial model. I know that I physically shot and bludgeoned the same person more than ten times in a siege level when I was playing the American campaign. This is an unfortunate detail in an otherwise impressive title.

Sound is just as good as its predecessor, with the sound effects taking the lion's share of the work in the game. Explosions, ricochets and the sounds of warfare sound extremely vivid in United Offensive, and it's even possible to identify the hardware deployed against you by the report of gunfire alone. The soundtrack for the game is still as orchestral and sweeping as the first, swelling during climactic battle sequences and fading into the background during quieter moments. If there was a weak section, it might arise within the vocal acting. Now, don't get too alarmed, because a majority of the dialogue is great. In fact, the comments by the flyboys in the British bomber stand out in my mind, especially when they start talking about women. However, some of the accents, such as the Russian and German, are either shaky or non-existent, which is a pity considering how solid the other accents are. I could tell that one of the American soldiers was from New York in the middle of a firefight, but a number of the German troops sounded like generic voice actors.

Single player and multiplayer improvements aside, United Offensive still suffers from some of the same problems that plagued the original game. First of all, the game can be extremely short, particularly on the lower difficulty levels. I managed to make it through in less than 10 hours, but your mileage may vary, especially on some of the harder levels. What's worse, just when you start to get a feel for a campaign or the soldiers involved within a stage, it's over. Since none of the campaigns intersect with each other, this can be quite jarring to your feeling of progress, especially with the limited amount of gameplay. Granted, there's a significant amount of maps and multiplayer available to pad out the gaming experience, but overall, but the single player still doesn't have enough to keep you coming back for more once you've beaten it.

The other significant problem is the AI of both the enemy and allied NPCs, which is inconsistent at best. There are moments when enemies are extremely deadly, resulting in a harrowing gameplay experience that is exhilarating for players. Other times, you may see opponents simply standing around or even hesitating in a jerky stuttering animation before launching into a full attack. Unfortunately, it's hard to actually tell which performance you'll get until you stumble onto it. Your squadmates aren't any better, because there are plenty of times where they'll kill everyone that moves and other times when they'll either stand around without firing a shot or quickly get slaughtered. In fact, aside from the times that you need to protect specific soldiers, moving within the middle of these troops can force them to be used as bullet fodder so you can observe where incoming fire is coming from. That way, you can snipe your targets without getting injured yourself. It's a heartless trick that reduces the attachment to the people on maneuvers with you, and almost breaks the believability of the "united" part of the gameplay, were it not for the fact that you forget about these people as you move onto the next level (or campaign, depending on how quick you are).

Apart from this, United Offensive is an extremely worthy successor to the Call of Duty Crown. Sure, the game is still a little short and the AI could use work, but the relatively expanded scope of the battles (thanks to the often overwhelming odds you'll face) gives you a better sense of being a part of a greater event, and the continually swirling action around you makes you really feel like you're in danger for a majority of the time. Add to that some new weapons, multiplayer maps and vehicles, and you've got an impressive expansion to 2003's Game of the Year.