Four ghosts at end of legendary
To get four ghosts you need to have the difficulty settings to legendary, you need to have killed the boss ( the robot ball ).
After you do so you need to exit the building, after you reach outside before you turn right to get the warthogs, you need to turn right and go down the ramp where you origanily came up from and when you reach the bottom of it look behind it and the four ghosts should be sitting their :].
Just make sure you don't boost up the ramp you might fall off because of the world shaking.
Gamertag: My Mum Hits Me1
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