Treyarch came under a bit of heat when it was revealed that the fifth installment in the Call of Duty franchise, World at War, would take players back to World War II, as opposed to the modern era setting captured so brilliantly by Infinity Ward in Call of Duty 4. Not that Treyarch had much of an option. World at War was already well into development when Modern Warfare was released to high praise last holiday. And with Activision’s policy of releasing yearly installments of their best-selling franchises, it was surely too late to jump on the modern bandwagon. So we’re back to World War II. As long as the game delivers, it shouldn’t matter should it? Well, let’s find out if World at War is a Call of Duty worth answering.

World at War’s single player campaign is set in the Pacific theater and Eastern front of World War II, with distinct Russian and American campaigns. In the Soviet campaign you’ll join the Red Army as Private Dimitri Petrenko, whose unit was defeated and executed by German forces. Along with Sergeant Reznov, voiced by Gary Oldman, you take revenge on the Nazis by sniping their commander and then proceed, three years later, to advance on Berlin, capturing the Reichstag and planting the Soviet flag to signify Germany’s defeat. On the American side, you’ll don the combat boots of Private Miller of the U.S. Marine Corps who, as the game opens, is being held captive by the Japanese and in line to be executed. After being rescued by Corporal Roebuck, voiced by Kiefer Sutherland, you join Roebuck’s unit in a series of incursions through the islands under Japanese control, culminating in a battle in Shuri Castle on Okinawa.

The Russian campaign is not unlike World War II operations from previous Call of Duty titles, but the American campaign is unique in that it marks the first operation set in the Pacific theater, and thus introduces a new environment and a new enemy. Instead of fields and warn torn villages, you’ll seize control of airfields and battle in jungles, caves and Japanese fortresses. The Japanese are guerilla fighters, employing trickery and ambush scenarios. You shouldn’t be surprised to find them hiding out in trees, in the tall grass or within their extensive bunker and tunneling systems. That’s where the flamethrower, one of the game’s new weapons, comes in handy. The flamethrower is equipped with unlimited fuel, though it can overheat with prolonged use, and is ideal for burning out enemies from bunkers. You can even set fire to trees and grass, though you have to be careful not to advance too quickly or risk catching on fire yourself. The snake effect of firing up the flamethrower from side to side is really cool and there are few things more satisfying than setting enemies on fire and watching them writhe in pain.

To add a little variety to the campaign, Treyarch has included a pair of vehicular missions. The first will have you command a T-34 Soviet tank, knocking out the German defensive line protecting Berlin. The other introduces a second playable character to the American campaign, Petty Officer Locke, a crew member of a PBY Catalina – a flying boat - tasked with taking out Japanese merchant ships, defending the Allied fleet against a kamikaze attack, and rescuing the survivors of a destroyed U.S. fleet. Overall the single player campaign is well executed and, for the most part, well paced.

When you complete the single player campaign you’ll unlock Nacht der Untoten, which you’ll get to know as Nazi Zombies. A cross between the Horde mode from Gears of War 2 and the recently released Left 4 Dead, this bonus mode has you defending a house from waves of undead Nazis. Every zombie you kill nets you cash that you spend to purchase ammunition, unlock and buy new weapons, or rebuild entrances to the house that the zombies have broken through. It’s a lively little diversion, one that can be played solo or co-operatively, but with only a single map available it won’t be long before you move on to the real meat of World at War, it’s multiplayer component.

World at War is the first Call of Duty title to feature a co-operative mode that allows up to four players to run through the entire single player campaign online. As an added twist there’s also a competitive co-op variation that includes a scoreboard to keep track of stats like Most Kills, Most Headshots and Most Revives. So even as you play together you can still compete with your friends. Competitive multiplayer is not unlike that of Modern Warfare, except the modern gear is replaced with World War II gear. Throughout the classic competitive modes like Free-For-All, Deathmatch and Headquarters, and new modes like Capture the Flag and War, you’ll gain experience and level up, unlocking new gear and earning new perks that you can customize your character with.

Some of the new perks include Fire Proof, to defend against flamethrowers, and Flak Jacket, to keep grenade kills to a minimum. When you go on a kill streak, rather than calling in a helicopter strike you’ll instead call in the dogs. The dogs are kind of fun. Not only will they lead you to an enemy’s position, they’ll attack that enemy as well. Some of the maps contain tanks, which lets one player drive and another man the machine gun turret on top. Tanks are available in about a third of the multiplayer maps but to accommodate for their presence, these maps are considerably larger and as a result will have non-tank lovers hunting around quite a bit for action.

World at War uses the Call of Duty 4 engine and Treyarch has put it to good use. The Eastern Front campaign is dark and gritty, a stark contrast to the Pacific theater that makes tremendous use of lighting effects. Everything else, from the character models and animations to the weather and smoke effects, are well produced. On the audio side you get some great Hollywood voice acting from Kiefer Sutherland and Gary Oldman as their respective squad leaders guiding you through each of the campaigns. Weapon sound effects are strong and the soundtrack is filled with appropriate military ballads.

While not on par with Infinity Ward’s Call of Duty 4: Modern Warfare, World at War is better than Treyarch’s last entry, Call of Duty 3. Even though it takes players back to World War II, the inclusion of a campaign set in the Pacific theater helps bring some freshness to the stage. The single player campaign is well executed, the Nazi Zombie mode is a nice surprise, and multiplayer, both co-operative and competitive, is sure to have virtual soldiers returning to the battlefield for months to come. It might not be what Call of Duty fans were hoping for coming off of Modern Warfare, but World at War does not disappoint.