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WARNING: May contain spoilers.

Act 1:
[AFP] Prolouge - Troubled past
1) COG Tag #1 - when you exit your room turn right and the door on your right is where the tag is in. Kick it open to obtain your first tag.
Act 1 Chapter 1 - Anchored
Twenty Dollar Bill - In your room, located on your desk.
Dom's Psych Report - First left out of your room
Requisition Form - Second left from your room
COG Tag #2 - After you defeat the wave of lambent enemies and right before or after you read the disk from your dad head over to where you see a orange rusted metal cargo with the gears of war symbol. Go around the other side if you look up at the bridge there should be a dead bod hanging from the side.. Look for the Gears 3 tag that fell from his body on the floor.
See the rest of the guide after the break and beware that there are some SPOILERS in this guide.

Act Chapter 2 - Abandon Ship
Silverbacks Manual - Located to the left of the silverbacks hanger bay.

Act 1 Chapter 3 - Homecoming
Journal: Home Of The Best Breakfast - In Town in the beginning as you enter the town before meeting the old man.
Child's Diary - Location inside the play set with the side.
Grocery List - Checkout counter #1 in the supermarket towards the right when enemies first appear.
COG Tag #3 - After kicking the fallen locker turn right and right again, there will be a room to enter.

Act 1 Chapter 4 - Helping Hand
Clipping, Times-Tribune - Once you pass the green doors when collecting your reward turn right head straight pass the blue metal cargo and then turn right again go all the way down and behind the brown metal cargo is a newspaper on the floor.
COG Tag #4 - After you receive the ammo supplies and open the gate turn left and left again to reach a dock platform and go all the way towards the end.

Act 1 Chapter 5 - MVP
Cougars Season Program - located upper levels behind the counter where merchandise are sold.
Cougars Player Handbook - Located just after passing the south gate in the lower level around the right corner.
Cole's Championship Ring - After Cole train's football moment head to the opposite side of the field.

Act 1 Chapter 6 - Hanging by a Thread
Bayonet - After passing the first gate on the bridge look for a metal carrier with a wooden crate towards the right. Break it.
Sightseeing Book - after using the motoar against the ship and pass through the bridge when you climb the ladder turn right and around the corner.
Toll Booth Tokens - When you first reach the toll booth the area where a locust is using the double retro lancer machine gun, before you go up the small steps to use it look towards the right of the stars and you will see some coins flashing.
COG Tag #5 - Once you pass the first toll booth area and you begin to head to the lower bridge, stay to the left and you should see a White Van where locusts will starting attacking. If you turn left before the white van there should be a ladder heading down. Once you head down follow the path until you see the first barricade, behind it is another Gears 3 COG tag. [/AFP]
Act 2:
[AFP]Act 2 Chapter 1 - Shipwreck
Tomatoes: A Beginner's Guide - Right the beginning after seeing the wild tickers there should be a metal cargo. Kick open the metal care and head inside.
Octus Medal Diploma - After moving to the second area where a second batch of enemies appear you will see two silver metal cargo. Behind the first metal cargo where the burning helicopter is.
Captain's Log - After you use the Siege Beast, there will be three locust who will pop out of the ground. Of where they popped up there will be a wooden crate up on some crates. Destroy it and the book will fall down.
COG Tag #6 - After Prescott dies look for a yellow metal cargo near by that has a Gears of War Symbol when you find it the tag is right behind that metal cargo.

Act 2 Chapter 3 - Forced Entry
COG Tag #7 - After shooting the guards without them sounding the alarms enter the side enters cd and head to the right where you see a flesh food tank and near the food is a basket. Push the basket over.

Act 2 Chapter 4 - Trench Run
Locust Hammer - After the balloon warship attacks you before heading up the ramp turn right at the stacks of boxes.
Queen Symbol - After meeting for the first time Queen Myrahh and defeating the enemies in the first area. Go through the first gate down the ramp and turn around you should see a gate towards your left. Kick it open.

Act 2 Chapter 6 - Airborne
Manifest - Once you meet up with Dizzy and the locust blow open the gate enter the next area and turn left and head all the way down.
COG Tag #8 - Before hoping back on the balloon warship Head up stairs in the second area and turn right until you enter a room from there turn left and beside the two crates. [/AFP]
Act 3:
[AFP]Act 3 Chapter 1 - Unbreakable
Anvil Gate Plaque - Right at the beginning turn completely around and it's located on the gate.
Watercolor Painting - At the beginning taker the right stairs up
follow the path and the right side you will see a room you can enter that will havh a large painting in the back.
Sam's Father's Medals - If you took the right stairs at the beginning follow the path until the very end where you will see two blue ammo box in a small room. Enter the room and the medals will be there. If you took the left stairs follow the path until you are at the front gate and on your left should be a walkway you can cross. Make tour way across the walkway and next to some steps on your right side there will be a room where you can enter and obtain the medals.

Act 3 Chapter 2 - Rescue
Journal - In the area where you fight the berserker. If you look behind the circular structure there should be a wooden booth where the item is located.
COG Tag #9 - In the area where you fight the berserker on the left side of the area should be a building with a Gears of War Symbol on the side look around the edges and be careful not to get ranover.

Act 3 Chapter 4 - Ghost Town
Stay Out! - After meeting the old man who planted the charges head down stairs turn right and head straight to the wall.
COG Tag #10 - When chasing the crazy old man after you break the wooden planks turn right and follow through to the next room where you will see a Gears of War symbol continue to the next room. Should be on your left side behind the sandbags.
Message - After defending against the lambent human in the market area. When u climb up the ladder turn left and head all the way down to the room.

Act 3 Chapter 5 - Brothers to the End
Air Raid Shelter Mercy A37 Maximum Persons 250 - After entering the church and breaking through the wooden planks turn left and jump up on the platform. Look towards the left. [/AFP]
Act 4:
[AFP]Act 4 Chapter 1 - Ashes to Ashes
COG Tag #11 - After the Ash Man pushes the box of tickers head up to the box and turn left there should a building that is being illuminated by a fire barrel. Go inside and inside the box is a dead man with his COG tag

Act 4 Chapter 2 - Crater
Journal - At the beginning of Chapter 2 head straight forward and look sightly to the right. You will see a destroyed building with a wooden door you can kick down.

Act 4 Chapter 3 - Hang'em High
Fuel Order - After you fight the first wave a lambent humans when trying to disable the safety release and before you enter the building, head over the the left side of the building on the balcony.
Old Magazine - After going up one floor and enter into the building again there are two enemies with torque bows in the burning room with a office desk that has the COG symbol on it. Destroy the box closest to the other room.

Act 4 Chapter 4 - Batten Down the Hatches
Tabloid - After seeing the first set of those centipedes there is a blue metal cargo toward the right of the area. There should be a open path on the left side.
Act 4 Chapter 5 - Bon Voyage
Bulletin - When choosing to get the sub rotor in the matinence bay head to the lower level turn left and there should be a room.
COG Tag #12 - When finding the fuel make your way across the first ship an turn right. Keep going until you make another right and behind the yellow cargo is the tag.
Drake: Frost 25, 12 A. E. - When opening the third hanger door and upstairs is a room with a Vulcan Gun. The item is next to the door entrance. [/AFP]
Act 5:
[AFP]Act 5 Chapter 1 - Home Away from Home
Pamphelt - When you make your way up the staris at the Station Platform where the first turrent is, if you look left by the arches you will see a book on the ground.
Assault Plans - You need a silverbacks for this. In once you are fighting outside in the rain when the enemies start firing motors at you. Head inside the cave and head towards the left side of the wall. There should be a metal gate you can kick with the silverback.

Act 5 Chapter 2 - Blackout
Schematics - When reaching the generator room you'll come across a office room with paintings on each wall. In the center is a office desk and behind it is a small red button you can press that will open the safe behind the panting towards your right.
COG Tag #13 - You need a silverback for this part. When the elevator gets stuck if you are facing the objective go right down the hall until you see a metal get that is broken down go inside you towards the right you will see a big metal door with a wooden plank. Kick it down the the silverback. (A silverback is located in a hanger behind some metal crates, look for a green button before you go on the elevator)

Act 5 Chapter 3 - Shattered Paradise
Money Stack - when you enter the hotel, heat down straight the first hall and when you can't go straight no more look towards your left and there should be a title on the floor you can break.
Diary - After destroying the dam, head upstairs and move towards the circle platform. Look for a book on one of those desk towards the right side.
COG Tag #14 - In the room before heading outside to Eliminate final siege beast crew head straight down the hallway until you reach the other side of where you entered and behind the benches is a dead body.

Act 5 Chapter 4 - Threshold
Memorial Announcement - at the beginning just follow the path all the way until you see a statue don't turn left into the next area.
Announcement - After you ride the elevator hit the call button and another elevator door will open, go inside and you should see it on the wall.

Act 5 Chapter 5 - Ascension
Brochure - After riding on the elevator, head down stairs and turn right, head all the way straight and if you look towards your right there should be a item behind the pillar.
COG Tag #15 - When you escape from Queen Myrah And ride the elevator to the next floor if you turn right you will see a Gears of War Symbol. Head over to the symbol and break the boxes. You will see the Gears 3 tag on the floor.
Fenix Research - after meeting up with your dad, in the same room look near the telescope is a desk that is where you will find your next item. [/AFP]