Act 2: Denizens
Chapter 2: Indigenous Creatures
#14: Gear Journal – When you find the second Rockworm, go left and cut through the vines. You’ll find a Grindlift, some ammo, and the journal here.
#15: Kantus Scroll – After you reach the top of the spire and kill the Reaver that appears, you can find the Kantus scroll behind the Troika at the back of the platform.
Chapter 3: Disturbing Revelations
#16: Locust Emblem – After your first encounter in this chapter with Drones, Wretches and Kantus, go through the doors and you’ll find the emblem near some ammo.
Chapter 4: Sinking Feeling
#17: Ilima Help Wanted Ad – Up the path, right of the Bloodmounts. It’s on the overlook that faces the snipers, near a Gorgon pistol.
#18: COG Tags: Hank Bissell – On your way out shortly after Cole saves you, the tags can be found just inside the building.
Chapter 5: Captivity
#19: Stranded Journal (Jennifer) – After releasing Baird from his cell, check to the right in a small alcove.
Chapter 6: Intestinal Fortitude
#20: Car Gold Magazine – Head left as soon as you start the chapter and you’ll find the magazine on the floor. If you’re getting the collectibles in order, you’ll get the second Collectible achievement, Pack Rat, here.
#21: COG Tags – These can be a little hard to see. After you find Carmine, but before you reach the ramp, look around on the floor to the left.
Act 3: Gathering Storm
Chapter 2: Origins
#22: Interoffice Memo – After blowing up the door, check in the small office to the right as you enter the new room. The journal is near a Boltok pistol.
#23: Memo (Dr Doug Sato) – After you use the security system to kill the wretches, this collectible is in a small room connected to the main hallway a few rooms beyond. You have to kick down a door in this room to reach it.
#24: New Hope Medical File – Later in the chapter, you’ll come across a room with a few turrets on the ceiling, with a switch at the back of the room to deactivate them. In the small room behind the switch you can find the New Hope Medical File.
Chapter 3: Rude Awakening
#25: Doctor’s Journal – After exiting the facility, DO NOT get on the train. Go right instead and go inside the small building. The Doctor’s Journal is on the floor at the back.
#26: Captivity Marks – Before boarding the final train, turn around and go inside the building at the back of the train yard. In here you’ll find the Captivity Marks scratched on a wall.
Chapter 5: Displacement
#27: Stranded’s Journal – After you fight the flame grenadier and destroy the gunboat, check in the middle of the area for a short set of steps. The Stranded’s Journal is at the top of them.
Act 4: HiVe
Chapter 1: Priorities
#28: Locust Terminal – The Locust Terminal is in the same room where you have to activate a terminal to search for Maria. DO NOT activate the first terminal yet. Instead, check the second terminal and you’ll get this collectible.
Chapter 2: Answers
#29: Locust Prisoner’s Journal – When the Mauler, Theron Guard and Drones have left or been dealt with, before checking the terminal, look to the left of it near the cavern wall to find the Locust Prisoner’s Journal.
Chapter 3: Hornet’s Nest
#30: Locust Jailer Document – Just downstairs from where you enter, turn right and head down the small corridor. You’ll find the Locust Jailer Document on the floor.
#31: Human Finger Necklace – This one can be easy to miss. After you defeat the pair of Grinders which come out of the large doors, you’ll need to roadie run to enter the small room with the Troika before the door closes. If you don’t get through the door in time, roadie run up the steps and across the room and you can get in the second door before it shuts. The collectible is behind the Troika.
Chapter 4: No Turning Back
#32: Locust Calendar – Up the stairs just after you start the chapter. It’s the round thing with glowing orange lights on it, against the wall.
#33: Locust Defensive Plans – After pulling the lever to extend the bridge, run across it and turn left. The Locust Defensive Plans are at the end of the hall.
Chapter 5: The Best-Laid Plans
#34: Locust Invasion Map – Before getting on the lift, proceed around the outside of the palace to find the invasion map in a little alcove just past the lift.
#35: Trinity of Worms – Before heading down the spiral staircase, climb the staircase on the right (where the Grinder was). This collectible is a pattern on the floor at the end of the hallway, beyond the stairs.
Chapter 6: Royal Inquisition
#36: Locust Tablets – Near the start of the chapter, the tablets are on the floor between two pillars. They’re to the left of the computer room, near the corner.