Samus symbolically became the mother of that Metroid sampling, which is seen on the trailer.
My guess is this game will include story from before Metroid 1 and span maybe the first 3 games. A Metroid trilogy remake with a prologue if you will.
Or, Samus is re-experiencing past events in search for answers in a VR simulator ala Assassin's Creed.(I think this is probably it.)







