Rhino Squad.

After a pretty uneventful elevator ride, you'll meet up with Raven Squad. They've apparently taken over the area and are doing some cleanup. You'll also get your first introduction to Tech Marine Strauss, who's probably the most full-of-himself guy in Rhino Squad. Make sure to have him patch up your armor while you're there. If you need some basic firepower, you can grab a MACHINEGUN, SHOTGUN, and some SHELLS that are lying around nearby. Once you're geared up, head through the door to leave this room.

Back outside, you'll see more Raven Squad members milling about. There's also a MACHINEGUN sitting on a crate if you need another one. Make your way around this area, which should look familiar, and you'll find some guys analyzing one of those Strogg Flyer engines. They seem pretty impressed with the technology. Here's a little secret: you can actually swipe those marines' MACHINEGUNS if you want. There are also some SMALL HEALTH PACKS in a nearby crate. Grab what you need and move on.

As you exit this area, you'll spot Private Salmon getting chewed out by Strauss. He's also rocking a MACHINEGUN, in case you were wondering. Continue on to the next room and meet up with Morris again. Follow him back to the trenches, open the door, and you'll finally link up with Voss and Sledge.