As it turns out the first DLC in D2 is about Osiris and as it seems the Stranger is a follower of him. I started thinking about the Stranger again and came up with the following: "Hold position, kill the engine and don't let them find you..." is what she says when we encounter her on Venus... What if she is talking to our future self? It could explain why she's always in the right place at the right time to "watch" us because we told her we would be there and we are going to play those missions in the DLC! I came up with the theory after watching the movie Predestination [spoiler]a future cop is trying to catch a criminal who turns out to be his future self (and another mindblowing twist...)[/spoiler]