Before you head out of your base, be sure to grab the Homing Missile Launcher, visible in the right corner of this screenshot [left]. Blast your way through any incoming Accountants or Lawyers with the shotgun, or use the Missile Launcher to wipe out a cluster of them. Take the back left route out of your base, and head along the mountainside to this first gun turret mounted on a roof. While strafing to the side, take aim and fire missiles at it until it explodes. This gun is sure to cause problems for you later, so it's best to blow it up right off the bat.

After taking out that gun turret, head inside the building and take control of the giant machine gun inside. There are two enemy gun turrets that you can shoot down below. Use this powerful machine gun station to blast apart those enemy guns, using either bullets or the machine gun's second feature: missiles. Although those gun turrets you're shooting at can't hurt you, enemies down there definitely will, so mow them down with bullets too.

Straight out of your base and down the hill (or right down beside the building with your machine gun), is body armor. Be sure to grab it, then attempt to make it up the hill. Use Homing Missiles to blast the swarm of enemies that are running down the hill. When running up the hill, be sure to fire at everything that moves, while continuing to move and zigzag yourself, making yourself harder to hit.

In close, blast away at the enemies who are trying to stop you. Run and gun with the shotgun works, as does mowing everyone down with the minigun. The Soviet doesn't seem to perform as well in this situation. You don't need a great bill of health as you push through - You just need to survive long enough to make it up the hill and reach the waterfall checkpoint. In the left screenshot as I'm battling some Accountants, the waterfall is just barely visible.

Once you reach the waterfall, it will be the location where you and your teammates will respawn after being killed. Behind the waterfall, is a medical kit to refill your health. You'll surely need it after your uphill battle. Coming up next, is another uphill battle with a gun turret firing at you. Stick to the wall out of it's sight, and run across as you get in front of it, making yourself harder to hit. I personally find it easier to get behind this one, and blast it from there instead of confronting it head on.

Destroy the Enemy Fuel Drums
Your next objective is to destroy the enemy fuel supplies. This involves blowing up six barrels scattered around the enemy base. - You'll want to destroy the enemy gun turrets first however.

This screenshot illustrates what you see as soon as you approach the enemy camp. It's been marked as a map, showing the locations of the six barrels, as well as two dangerous automatic gun turrets.

Two barrels are in open view, while the others are somewhat hidden. There's one inside the left building, and another one way at the back left against the mountain. There's another one on the roof of the right building, and one behind and to the far right of the right building.

Before destroying any barrels, you'll want to rid the area of those hazardous gun turrets. Fire away with the Homing Missile Launcher to take out the guns mounted on each building. Keep firing missiles until you know the gun placements have been knocked out. Once these turrets are destroyed, you can go to work blowing up the barrels of fuel. One barrel is located on the roof, and depending how many missiles you launched trying to take out the mounted gun on the roof, the rooftop barrel may have already been destroyed.

The order in which you destroy the barrels is personal preference, so you'll probably find an order that works best for you. Once you have all the locations memorized, you can make decisions on the fly... If a whole bunch of enemies are surrounding one part of their camp, it might be better to head to the other side and take out those barrels first.

Something that may come in handy, is the body armor that's hidden on the roof. To get up there, you'll need to take the ramp inside the right building. I usually leave the roof barrel for last, that way I can snag the body armor while I'm up there, and have some bonus padding for my trip inside the enemy lair.

The two entrances to the enemy computers are through the right building, or through the cave entrance by the far left barrel. Either way, once you're inside, you need to blast away at the row of computers, preferably with the Homing Missile Launcher. There are a few tricky computers off to the left side, but keep in mind that every single machine needs to be destroyed. Once this task is accomplished, you've won.