There are 3 Dead Ghosts to be found in The Terminus. They can be collected only during the mission The Queen's Ransom. Each Ghost can only be collected once per account.
Ghost 1[edit]
The first Dead Ghost is found just after you take the Gravity Lift up from the The Juncture. Turn around and look behind the lift. You will see a structure behind the lift.
Jump over to that location. Climb up to the top. On the right you will find the Dead Ghost.
Ghost 2[edit]
This Ghost is found after you complete the Platform Puzzle section of the mission. Jump up onto the raised portion of the platform you land on to your left. On top of that you will see a second raised portion. Head over to that and go around it on either side.
On the far side of this platform you will find the Dead Ghost. It sits in a small nook in the lower portion behind the raised part.
Ghost 3[edit]
This Ghost is found after you complete the Platform Puzzle section of the mission. Head to the right and start fighting through the enemies. Having cleared this area, start going forward until you see this narrowed portion of path:
Jump up onto the right-hand side. Do that once more and you will find the Dead Ghosts.