Gears of War 3 Game Guide

Act Three: Chapter 4 – Ghost Town

Follow the path, grab ammo along the way, and eventually you have to start
disarming bombs. By the second one is a frag, and before the third is a window
you can jump through for ammo. After you meet the crazy guy, there is a Sawed-
Off shotgun by the door, but leave it and go up and down the steps to get a 
Scorcher near a note. The scorcher is a flame-thrower and very handy upcoming.
After you open the boards to the next building, you can grab flame grenades and
a COG if you go through the kitchen. Get the ammo by the dumpster if you need
and head into the sewers.

Burn the first one and then the ones coming down the sewers; they may also be
behind you or not. Just head forward and your group will reunite at a pit where
you fend off the Lambent and wait for them to burst out of a wooden barricade 
on the left. Fry them all, turn the valve, open the door, grab grenades if you
need, and take the ladders up.

Head to the other side and get on the Vulcan. It has a fairly wide berth, so
just shoot when you see them, stay back a bit, and scan the area. There will
be two concentrated waves, one to the left and one to the right, so pay 
attention to the chatter. Use up the Vulcan, use up the scorcher, and then blow
your lancer ammo until the encounter ends. Grab some ammo and go up the ladder.
Head left to find a note and head down the steps to end the chapter.