User blog comment:EmpyreanSmoke/Supernatural Q&A/@comment-3045936-20151110045154

Doubt you can answer this, as it might break spoilers. Did the Darkness, ever affect the worlds, outside of the Mark? Like did Agnes see into the Darkness, to learn about curses? As an example. As Lucifer's cage has 660 seals on it. And still could talk to, Yellow Eye could through a dead nun. Like my question is. Did the Darkness' cage ever have cracks in it. To where it could affect the outside world, but not through the Mark of Cain.