New player here. Russia, 1550, and I am proceeding with incorporating Central Asia. Problem: Terra Incognita. Without taking Exploration, how do I lift it? I know about the Siberian national idea, but that's kind of slow and limited. I am even in the absurd position of having a vassal (Nogai) that is partially hidden from me. I also was thinking about sending a couple armies east to annex Manchu & colonize from both directions, but can't get there. Any ideas?