"Kill ghosts with E-Gun" is a mission objective in the side mission "Sub-Level 13: Part 2" in Borderlands: The Pre-Sequel
There are 5+ Ghosts scattered throughout Sub-Level 13
One of the Ghost can be found in the same room as the first recorder. Look around the device on the Southern wall. Look up toward it to see the Ghost circling around it. Just wait for it to come around or hunt it down and blast it with the E-Gun.
When you locate the Cargo Fast Travel station, you will encounter another Ghost. It will quickly be joined by 2 others.
After you take out the first set of Ghosts, another pair of Ghosts will appear. Take them out to finish this objective. More will keep coming until you destroy the control consoles.
Sub-Level 13: Part 2 Mission Objectives
- Kill ghosts with E-Gun 0/5
- Find first record
- Find second record
- Locate cargo fast travel station
- Input 1-9-8-4
- Destroy consoles 0/3
- Find space-fold inverter
- Exit Sub-Level 13 or Use inverter