Hi there, Thanks for reaching out. Just to confirm, is there a chance you've already acquired these last two Ghosts but haven't yet placed them around the Outpost? The act of placing the Ghosts should cause the triumph to update. Alternatively, if that's not the case, we would recommend consulting a guide of your choice to determine how to find the remaining Ghosts. That said, if you believe you're experiencing a bug, please capture a video that shows the issue occurring. You can upload the footage to a public video hosting site, like YouTube, and we’ll be glad to take a look.