When you come to a large room where two soldiers are fighting a... big thing, dont bother helping them. Instead, run over to the tunnel on the left. Conspiracy theory: that G-Man is everywhere. Once ...

Gonarch must be the name of the gigantic mommy headrab which you will quickly confront on this level. Its weak spot is that big hanging sac hanging underneath it. While firing away, be sure to keep ...

After taking care of the doggies, you can either jump over the fence and lose some health in the process, or shoot the big electrode to open the door. In the next room will be a new type of alien ...

That test didn't go off too well. Get out of here by using the broken retinal scanner to open the door. Pick up the health kit, and watch the scientist administer CPR if you're so inclined. Start ...

Go down the corridor and around the bend to the right. From now on you'll have to watch out for little red laserbeams crisscrossing your path. Tripping them will activate painful sentry guns. Jump ...

After some soldier firefights you'll come to a nice big dam area. You can bypass all of this and just jump into the water if you want, but it's more fun to blow up the artillery gun and the helicopter ...