Yes, Yes, you have just seen the pretty cinematic (or skipped it), and now you are here, your buddies are dead. Just you, armed with a pistol, and the artifact that looks like a heart with some metal and a grenade pin attached to it. It isn't beating just yet, but have patience.

First off, you find yourself in a corridor with the artifact, and your pistol, feel free to look at the random emails and videos on your PDA. Now, walk forward and have some crazy "vision" of the room filling with blood. Ooh, scary. Anyway, take the next right and find your trusty shotgun, along with a dead marine and shells.

Now, go back and continue down the hallway you were just in, run through and you'll witness your first enemy: a forgotten. Take him out with whatever method you find suitable [TIP: if you can time it just right, you can use the fists to punch the Forgottens away. one hit kill, no ammo consumed. highly recommended]

Keep walking down the hall, and go left as to avoid the void. Follow the hall down to find a large cavern with a void on the left side of it. Go to the Power Cell Generator and remove the power cell. It will become an inventory item. Continue forward, to be ambushed by more Forgottens to the left and front. Keep going and pick up the videodisk about Power Cell Generators. Its very educational. Then turn around to the 2nd Power Cell Generator and insert the Power Cell into it. A chain of platforms will begin to move up. Jump onto one of the Platforms as it comes up. Don’t jump too soon, or it could mean ouchie. As you ascend, you will see a rock ledge with some armor on it, if you feel like it, jump onto the ledge and grab the armor, unless you like to be a speed demon in gaming. Hop back onto an upcoming platform and resume your ascent. Beware, there are a couple of Forgottens and an Imp waiting for you there [TIP: A very well placed shotgun round can kill the imp in one hit. strafe left and right to avoid fireballs, then sprint into the Imp's Face and Blow his head off. Only one shell required. Not sure about nightmare mode, I’m playing this on veteran]

Continue toward the hallway around the corner. Run down the corridor, and you will find a machinegun in the middle of the hall, along with a door to your right.

Behind this Door is a rather large cavern, you will encounter more Forgottens and 2 imps, no biggie. Directly ahead of the entrance, you will find an exit covered by large brick. Hop over the bricks and to the door.

Just before you reach the door, a cinematic will play, showing a marine giving an Imp "a taste of his own brand", who gives you the grabber. [TIP: Grabber is VERY efficient in killing Forgottens! however, don't try to employ the "plasma grabbing" technique that marine used, its not very useful, especially when you are surrounded by Imps and Vulgars]

Feel Free to play with random objects with the grabber to get the feel of it. All you do is press and hold the FIRE key, letting go propels it, while holding on to it eventually drops after about 5or so seconds.

Go down the Stairs and get rid of the boxes in your path with the grabber. Go through the opening and into the cavern that awaits. You will encounter some Forgottens, kill em, then keep walking down, and you'll find a big cavern, take a left and you'll find a large stairway with voids on either side. Kill the Forgottens, and continue up the stairway. You will find a door directly in front of you, beware, a forgotten is waiting for you behind the door. Go down the hall and get ambushed by yet MORE Forgottens in small crevices near the floor on both sides of the hall. Then continue to the end of the hall and kill some imps and a forgotten waiting for you. Take a right and you'll find an elevator exit to Erebus Dig Site.