| Unlockable | How to unlock |
|---|
| Chapter 2 | 1. At the start of the chapter, before entering the building, destroy the Ork barricade opposite of that building to find it. |
| Chapter 2 | 2. At the start of the chapter, after your conversation with Leandros and dealing with the ambush by the Gretchins, you will find it on a patch to the right, by some sandbags. |
| Chapter 2 | 3. In Trenches, in the second bunker, just after you meet Lt. Mira. |
| Chapter 2 | 4. In No Man's Land, look near the grenades in a small room after you enter the building from the courtyard. |
| Chapter 2 | 5. In No Man's Land, after exiting the building, look for it on the first bunker to the left. |
| Chapter 3 | 6. At the start of the chapter, when you are inside the fortress, look to the right, and destroy the barricade that is next to the ammo. Go inside the room to find it. |
| Chapter 3 | 7. In the Armory, take the elevator on the lower floor to find it ahead of you by some ammo. |
| Chapter 4 | 8. In the Train Station, at the end of the first walkway, just before you head to the train, turn left to find it. |
| Chapter 5 | 9. At the start of the chapter, after seeing the Crane and finishing the Orks in the lower area, look behind the crate to the right. |
| Chapter 5 | 10. In Cargo Bay, after you take the elevator down, you will find it on the walkway towards the manufactorum. |
| Chapter 6 | 11. At the start of the chapter, when you are on your way up to the elevator, take a walkway left that is going down with some grenades to find it. |
| Chapter 6 | 12. At the start of the chapter, just before activating the bridge, go to the ramp to the left of the door. |
| Chapter 7 | 13. At the start of the chapter, in the sewers, after your second encounter with the Works, you will find it in the left sewer entrance. It is opposite to the exit. |
| Chapter 7 | 14. At the start of the chapter, before the elevator and after you drop down to the catwalks, look behind a barricade on the left to find it. |
| Chapter 8 | 15. At the start of the chapter, before entering the street, drop down into some rubble, and look in the hallway behind you. |
| Chapter 8 | 16. At the start of the chapter, after your encounter with Shoota Boyz and entering the building, look for it in a room to the right. |
| Chapter 8 | 17. Go upstairs from where the previous Skull was to find it in a room on your left. |
| Chapter 8 | 18. In Street Warfare, first underground tunnels, in an area to the right with ammo. |
| Chapter 8 | 19. In Street Warfare, before the ramp up, after the fight with Orks in the big room, to the left of the ramp. |
| Chapter 8 | 20. In Jump Pack, after you jump up to the first platform, follow the path to the right, and then jump up to next level to reach it. |
| Chapter 8 | 21. In Jump Pack, after your first encounter with Orks, go past the crashed Rok, and to the right of the stairs. |
| Chapter 8 | 22. In Jump Pack, after the fight with the Wierdboy, head down the stairs to the right to find it by the grenades. |
| Chapter 8 | 23. In Jump Pack, after exiting the area with the Weirdboy, before heading down the stairs, jump over some rubble straight ahead to reach it. |
| Chapter 8 | 24. In Jump Pack, in the next area that is two level above you on your right, after climbing up the small stairs. |
| Chapter 9 | 25. In Kalkys Outskirts, take a left from the destroyed bridge to find it at the end of the canyon. |
| Chapter 9 | 26. In Kalkys Outskirts, look near where the canyons converge and the crashed Valkyrie is. |
| Chapter 9 | 27. In Kalkys Outskirts, before heading up the ramp after the second pipe, it is to the left of the ramp. |
| Chapter 10 | 28. At the start of the chapter, when you come across an intersection after destroying the pair of Servo turrets, go left instead of right. |
| Chapter 10 | 29. In The Labs, it is in the smaller lab with a turret. If you are out of ammo, you can destroy the turret for ammo. |
| Chapter 10 | 30. In the Security Room, kill the Shoota Boyz, then place the power source in the center of the room, and take the side walkway with the destroyed door to find it nearby. |
| Chapter 12 | 31. At the start of the chapter, when you are supposed to enter a pipe from the bridge, go upstairs, and turn left to find it at the end of the hallway, behind the barricade. |
| Chapter 12 | 32. At the start of the chapter, after getting the previous Servo Skull, follow the hallway in the opposite direction. There is a large room with ammo past the stairs behind another barricade that you will come across. It is inside this room. |
| Chapter 12 | 33. At the start of the chapter, after the battle between Chaos and Orks, go upstairs to find it in the room to your right on the upper floor. |
| Chapter 12 | 34. In Enemies Aplenty, re-unite with Lt. Mira, and look for it near the back wall by some ammo. |
| Chapter 12 | 35. In Enemies Aplenty, take the elevator, and go down the hallway until you reach another hallway to your right. To the right of that hallway is a small room with the Servo Skull inside. |
| Chapter 12 | 36. In Bastion Primus, when you go back to the original hallway from the elevator, at the end of that hallway, it is down the catwalk by some weapons and a shrine with a Plasma Gun. |
| Chapter 12 | 37. In Bastion Primus, after you break apart from your squad and Lt. Mira, you will find it in a trench near a weapon cache. |
| Chapter 12 | 38. In Bastion Primus, you will find it before the battle with Warboss. It is under the bunker, behind some crates near the ammo cache and final door. |
| Chapter 13 | 39. At the start of the chapter, you will find it before exiting the catwalks area, through the door on the left, just before the ramp. |
| Chapter 13 | 40. In Free The Titan, it is in the left corner of the room after exiting the elevator. |
| Chapter 13 | 41. In Free The Titan, when you break apart from your squad, go up the ramp to the left of the elevator to find it in the side room. |
| Chapter 13 | 42. In Free The Titan, it is in a small room to the left of the walkway where you encounter the Chaos Drone. |
| Chapter 15 | 43. At the start of the chapter, exit the elevator, and look to the right of the ammo and weapons to find it. |
| Chapter 13 | 44. In Traitor's Arena, it is in a destroyed pipe to the right of where you fight Renegades, which is just before you go outdoors. |
| Chapter 13 | 45. In Traitor's Arena, after you fight with Bloodletter Daemons, it is near the weapons before you go up the stairs to the next area. |
| Chapter 13 | 46. In Ascent, after you meet with Chaos Psyker, look for it in a hallway on the left. |
| Chapter 13 | 47. In Vertigo, you will find it on a floating platform above the Chaos Space Marine just after you exit the hallway. |
| Chapter 13 | 48. In Vertigo, after your encounter with Chaos Drone, look for it in a small room to the right. |
