This is another massive level teeming with humans, bugs and multiple paths to take. You begin on a crumpled highway overlooking a vast stretch of lava-laden rocks, but before you head down there, you should make some tactical rocket attacks. First get through the humans and activate the data post (sniping with the rifle and using grenades are excellent methods). You'll see a rocket launcher sitting atop some crates - that's six rockets for sure. But, there was a rocket soldier up here a second ago, and occasionally he'll drop another launcher. If you're lucky enough to net six more rockets, you're in great shape for the task ahead. If not, well, six will do, but it'll be a bit harder.
If you look east, you'll see a tall structure with two missile launchers poised and ready. Right now, they don't know you're here. Toss two rockets at 'em, then look directly below their smoking ruins for two more launchers. Odds are they notice you by now. Take them out by jumping straight up and firing in midair - you should never leave the safety of the street until these launchers are gone. Now turn your attention to the two Vital Suits that are standing on top of metal platforms. Each should take two hits before falling to the rocks below. You should still have four rounds left, so use them to finish off one of the Suits and then clear a rocket-tossing soldier hiding by a truck to the east. Save the last Suit for when you're down there - you can certainly use the extra T-ENG it drops. If you only had six rockets to start with, just make sure you off the missile turrets and choose your own final targets.
The best way down is the path to the south. It leads you to the rocky bottom without attracting a lot of attention. Exchange your (now empty) launcher for one of the rifles that should still be lying around. Snipe the three enemies on the sloping southern pass (one may drop more rockets - leave 'em for now) and stop. See all those soldiers? Snipe as many as you can so they don't rush you later. The moment you set foot on the rocks, it's on. Therefore, stay on the sliding path until you've cleared most of the troops. Hint - those metal platforms both have a lot of explosive barrels sitting out in the open.
From this point, it's all up to you. Use whatever Vital Suit you want, proceed however you see fit. Just remember to advance slowly and not attract the whole armada of enemies at once. Take your time, get off some good on-foot rocket attacks and keep collecting energy. A lot of Suits will ignore you if you're slamming them with rockets from far away, so keep that in mind. The only other point of interest is the "R" token found on the northern tip of the broken highway by the pouring lava. Shoot it from any point you see fit.
Your goal is the door to the underground base - it's to the northeast. Inside you'll find an enemy VS and a slew of those floaty, explosive Akrid from a few missions past. Hop into the grating below and shoot the "A" token in the northwestern corner. Your VS situation is probably pretty dire at this point. Just ditch it and keep going. You'll find another data post in a shaft ahead (pop the Akrid for a room-cleansing explosion) along with another batch of rockets. There are two paths here - one is the nearby elevator shaft that leads to a VS, and another that ultimately drops you in the same place but with a tank VS instead. Near as we can tell, you can't get the "B" token without a tank drill, so we'd recommend you keep one around. Either way, you'll be able to get the "I" token on a large ledge that also hides a jumper VS. If you're having trouble, it's also a room with those spiky, plantlike Akrid. Hit the images tab for more hints if it's still unclear.
The hallway is stacked wall-to-wall with bugs, so any VS is invaluable here. You know how to take 'em out, so do it and move on. Consider taking the new VS located at the bottom of the next chasm - the upcoming exploder Akrid swarm will bang you around for a good while if you're naked to the wind with no bipedal death machine. The hallway ends with another rockslide that only the tank VS can break (if you have one, break through and find the "B" token). Luckily, there's also a small passage to the left you can take as well, one that happens to contain the "O" in its southwest corner, right behind the energy silo. Up ahead is a room with three exits. Bust down the lower western door and use your current VS to take out the gigantor Akrid on the other side. You also see the "W" token in the gateless hangar, hiding in the dark corner. If you're low on energy, go ahead and activate the data post in here. Once that's done, and all the smaller bugs are toast, grab and arm the VS on the second floor of the main room and head to the northern doorway. It's too high up for some Suits to jump, but this new one will be fine.
