Activate the hub station to rotate the tram on to the correct course.

Guide your way through the Hub Controls and Hub Monitoring rooms in Quake IV. Learn how to defeat tough Strogg enemies and activate the hub station to rotate the tram.

Alright, so you've made it to the part where we need to get that tram moving. Cortez will lead the way to the "Hub Controls" door. Keep an eye out for a small health pack nearby – grab it if you need it.

Once you're inside, get ready for a fight. You'll need to take out four Strogg Marines and a Gunner. After that, check out the crate in front of you; it’s got some small health packs, shells, and clips. Move into the next room, and this is where things get serious: five Tactical Transfers and a Light Tank are waiting. If you want to play it safe, you can hang back and snipe while Cortez handles some of the action with his shotgun. You'll also find two slugs, a large health pack, and some armor shards stashed in a crate around here. Keep pushing through the next door, and be ready to deal with two more Tactical Transfers and a Gladiator. Your Rocket Launcher or Railgun will be perfect for this. Just when you think you're clear, two Strogg Marines will pop up from above.

Now, look to your left and click on the "Expand" panel. Pretty fancy bridge, right? Cross over it and go through the door on the other side. Things get a bit quiet now, don't they? Follow this passage as it leads you up to the upper level. Up here, you'll find a good haul of supplies: grenades, nails, batteries, shells, and clips. Head into the door labeled "Hub Monitoring." Take a look at the monitor – yikes, that marine’s face is pretty messed up. Keep going until you face a single Strogg Marine, and you'll see a health station on your left. Finally, enter the hub control room. Find the smaller panel and simply click the left arrow to rotate the tram car. Bummer, looks like the track itself is damaged too. Dammit.