So I'm going to be running Kingmaker after our group finishes Iron Gods. (I'm not the GM for IG) I want to familiarize myself with as much of the area as possible so I can give the players as much information as I can. Is there any material that pertains specifically to the Kingmaker AP that would be useful.
For example when I ran RotRL, I bought the Varisia and Magnimar books, when I bought the Iron Gods stuff, I bought the Numeria book, People of the Stars, Technology Guide, etc.
I just want to know if there is any material that can help me with Kingmaker.
I plan on buying Ultimate Campaign and Guide to the River Kingdoms, any other suggestions?