He looks a little surprised and amused. "Knowledge isn't forbidden. Try the Library of Cagliostro. Beyond Study of Time and How to Contact Dormammu and draw power from the Dark Dimension. Also that - extra-dimensional beings can't quite properly exist in... not their own universe, and since I destroyed mine... I expect at some point I just - will cease to exist."

He sounds a bit resigned to this, as though that were the fate he had sentenced himself to - that the Watcher could not, would not, interfere.