Enter the room. Get up the stairs. Shoot the enemies down there to help Cole. Get down and finish the remaining Drones. After the

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cinematic, grab the ammo and go up the stairs opposite from those you came down from. When the door opens, get in the corridor and prepare for some tough fighting. I preferred the shotgun for this battle. You'll face a new type of enemies here - Wretches, which are basically your classic fast leaping, annoying small creeps that are hard to aim at and deadly in close combat, a popular type of nemesis in the shooter genre. Also, here is the eighth COG Tag, right behind the table near the sealed window.
When the door is open, pick up the ammo and go through it. Grab the Hammer of Dawn here, it's a weapon near the window. It is used by holding shoot button on the target until fire rains from the sky, or rather, a satellite. It's a very situational weapon that works only on special occasions, don't be shy about dropping it when it's not needed anymore and picking something more useful.
This time use the Hammer to kill the Seeder - a huge spider-like creature found outside - as well as all the other

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enemies in the area. Then get over the bridge and run after your teammates to the opposite entrance. There is some ammo near the water if you need it.
Proceed to the next room. Some grenades here. Go through the door, get on the balcony, fight off the Wretches and use the Hammer on another Seeder. Some ammo can be found here. Proceed through the door at the left side, turn left and go down. Continue moving, grab the grenades and reach the dead Seeder. After the dialog, enter the door to the left and run until you reach a bigger room. Here you'll have to fight some more Wretches and a Drone. Continue moving. When you walk down the ladder and find the body, turn right and pick up the ninth COG Tag. After the dialog, get up the stairs to the left.