Call of Duty: Modern Warfare 3 is undoubtedly one of the most anticipated games of the year. With over 23 million units sold in its last iteration, it continues to cement its position as the top of the crop for modern shooters.

At the first annual Call of Duty XP event in Los Angeles, Shacknews grabbed a seat with an Activision representative to play the game's new Survival mode. Essentially a take on the increasingly popular "Horde" mode from Gears of War 2, Survival pits two players against waves of increasingly difficult enemies across all of the game's 16 multiplayer maps.

As a co-sponsor of the Call of Duty XP event, the only platform available for demo is Microsoft's Xbox 360. The game itself controls exactly the same as it has in the past.

The major difference in this multiplayer mode are how loadouts and stream bonuses work. Rather than bring a full arsenal into a match, players begin with a pistol and must earn cash to purchase new weapons and equipment. Cash, which each player earns separately but can share, is gained by killing enemies, with extra scratch doled out for headshots and multi-kills.

The map I played was called 'Resistance,' which has an Eastern European architecture vibe. The map has open courtyards and bombed out buildings that intersect, giving players a handful of options for attack. It's a pretty good size for battle. Later I played the same map in a game of Domination and felt that it worked extremely well, too.

After the initial wave, players have access to the weapons armory in order to purchase more ammo and weapons. Each weapon is broken down into their familiar type (pistols, assault rifles, etc.). Players can also pick up weapons from downed enemies throughout the map.

Over time other options become available. Around the fourth wave of enemy forces my partner and I were given access to the equipment armory to purchase things like grenade ammo and C4 as well as access to an air support armory that gives players access to things like air strikes.

Each item available in the three armories is priced according to their power. A major support system like Delta Squad, for example, is priced in the $3000 range.

Delta Squad was by far my favorite option. This allows players to call in an AI controlled squad of three Delta Force commandos, which rope into the level via a transport helicopter. I was surprised at how effective the squad was. My impression when I was told what the support bonus did was that I was calling in a group of cannon fodder, that's not the case. They are effective and can support players quite aptly.

When players are downed for the first time they are given a Last Stand bleed out meter. So long as the meter fills up over time--something that only happens if you do not continue to be shot--you can get up and brush yourself off. Following the first fall, it's your teammates that must revive you. Once both of you are downed and no bleed out is available, the game is over.

Waves can get very brutal, very quickly. By wave five players are pit against two attack helicopters, for example, that can cut you down to size in seconds. At wave ten, a Juggernaut was dropped. This enemy is covered from head to toe in Kevlar and sports a riot shield and an extremely powerful weapon. Our best tactical option was to blind him with flash bangs and drop C4 and Claymores near his position, while popping off a few well-placed headshots.

There's a good balance of constantly going back to stationary positions, like crates with access to weapons, equipment, and air support. Players can set up some turrets to cover positions, but enemies will come from all sides. They don't run right at you either. They have a tactical mindset that increases in intelligence with each passing wave.

Survival is extremely fun. It would be great with more than two players, of course, but two members on a team offer more opportunity for tactical decisions. It's also brutally hard. I imagine adding two other players would make the ability to revive each other much easier.

I had a blast with the mode and look forward to playing it again when Modern Warfare 3 launched on November 8 for the PC, Xbox 360, and PlayStation 3.