Step on it as it turns and jump to the next belt. Ride it into the next room and talk to Voss there. When the scene is over, head down the next set of stairs and you will be told to meet at the waste disposal facility. Make a U turn in the room and go through the blue door. Ride the lift up and enter the next room. Clear it out of enemies and make a right at the far end. Go through the next room and kill the Strogg medics and make a right. Enter the large round room and make a right to the door there. Call the lift and ride it down. When you get off, kill the Strogg here and then enter the small crawlspace to the right. Grab the rocket launcher and the hyperblaster and continue crawling through. Follow the parasite that runs past and come out into the large open room. Kill the parasite and the few enemies it teleports in and then head for the large orange door.

Construction Zone

Head outside and you will see a walker mech suit down the ramp to the left. Hop in it and start to take out the flyers and the balls they drop. When they are toast, continue to the left and head for the archway and enter it. Continue forward killing the Stroggs that show up and make a right at the intersection. Make your way to the next door and go through. Follow the track and take out the flyers here and head for the next door. Go through and you will just keep moving forward through the small interior and come back outside. Destroy the turrets that get dropped and continue through the archway to the left. Enter the tunnel there and make your way through until you come back outside.

Kill the turrets that are dropped here and make your way to the left and then go to the right and you will face a slew of enemies. Use the machine guns here to take them down quickly and not have to wait for the missiles to reload. When you reach the ramp, make a left and walk up it and into the next area. When you walk to the end of the pipes, there will be a harvester that appears. With the walker and its rockets, you can target certain areas on the Harvester. Target the two front legs and it destroy them. Once they break, it will crumble and die. Continue past it to the disposal facility and hop out of the walker. Cross the catwalk and enter the red door.

Dispersal Facility

Watch the scene and then kill the Stroggs waiting to ambush you. Grab the railgun and enter the door on the right. Follow the hallway around and kill everyone in sight. When you reach the lift, hop in and ride it up. Head out the door there and there will be a Harvester to the right. Use the pillars and boxes for cover as you run down the catwalk to the door at the end. Go through after you crouch through the debris and enter the green lit hallways. Kill the Stroggs here and continue to the next room. Walk up to the elevator in the center and use the control panel to call it. When it comes, hop in and ride it down. Go through the door there and wipe out the Stroggs waiting around for you. Go through the door to the right and follow the corridors along through each door.

Head up the stairs and through the next rooms and you will come to a fence. A Strogg will jump on it and climb through the top and drop down on you. Take him out and make your way to the right and jump down the stairs and take out the Strogg along the way. When you reach the bottom, go through the door there and enter the brightly lit gear room. Head through the door on the right side of the room and continue forward. Head left and follow the corridor until you come to a room with a large beating heart. To the left and right of the heart, there will be platforms that have voltage control panels. Use both to stop the heart and then jump back down in front of it. A grate in the floor will open and some repair bots will come out. Jump down the opening and crawl into the pipe there.

Recomposition Center

Head forward and kill the Strogg there hooking up marines. When he is toast, you will hear someone yelling for help in one of the cells below. Walk to the control panel between the cells and click the number 4 cell and the center to release him. When he comes up, he will adjust your nail gun to allow you to have a seeker mod. Head for the stairs on the right and follow the passage to the left and through the door there to the barrel storage. Sasaki will tell you to find the barrel activation so that you can stack the barrels and reach the access at the top. Make your way to the door on the right at the far end and head through. Head right down the next passage and you’ll find some Stroggs here.

Kill them and head up the stairs. Make your way to the right and continue to the right until you come to the door with the green lights. Go through and you will find a marine getting zapped by a lightning gun. Use the control panel to shut it off and then grab the gun. Give the marine a zap of your own and continue to the right and head through the next door. Enter the room at the end and use the control panel there to turn on the barrel activator. Once you have that done, you’ll need to enter the Sterilization room on the left. Follow the corridor until you come outside and make a right. Head left across the catwalk and take out the few Strogg there. There will be two up on the girders across from you, so use the railgun to pop them. Head down the stairs and make your way left and into the door there.

Continue on and you will come outside again. Kill all the Strogg in this area and the door to the far right will open. Head through it and you will come to the sterilization chamber. Make your way around the room to the far side and use the control panel there. Hit the system reset button and you will need to make your way back to where Sasaki was. When you get there, he will get dragged off so it’s up to you. Press the flat panel button on the console and then the up arrow. Press the barrel button and then the down arrow to bring the stack of barrels to you. Jump on the console and then jump on the higher part to the right. From there, jump on the barrels and then jump over to the broken catwalk. Make your way to the red door and go through. Kill the Strogg that climbs out of the hole and jump in it yourself.

Putrification Center

Ride the conveyor belt straight along and eventually you will come to some of the belts that have large canisters that try to push you off. Make your way past those and continue through the next door. Keep riding along the conveyor belts until you come to the drop off. Drop down to the next set of conveyors and watch for the giant needles. After that, hop on the next belt and watch the large sawblades. Go through the door on the right and ride the belt a little way and hop off to the right. Go through the door there and continue along to the next belt. Watch the flamethrower and the next set of needles and then hop to the platform on the right.

Jump on the railing there and then jump to the belt there and ride it to the end. Drop off it and go through the door straight ahead. Kill the Strogg on the catwalk ahead of you and make your way right. Continue along and go through the door on the right to enter a fleshy pulsating hallway. Continue to the end and you will come face to face with the Stroyent Processing creature. Head to the right and go through the two doors there to get into his chamber. As you run past him to get on the left side of him, watch for his hooks that he flays out at you. When you reach the far side, use the control panel to spray him down. When you do, he will break the glass behind you. Jump through and go through the door there and enter the next room.