for anyone studying the Apocalypse.  How do I do it?  I don’t.  I let the experts do it,  Even they don’t know how to count kings but they do know how to count dynasties.  First you have to figure out who the beasts are and that is also a challenge.  The seven kings, the ten kings, and the two beasts are all in chapter 17 of the Apocalypse along with Babylon the Great and it is a mystery.  Rome was not a mystery.  Peter knew that and he knew those he was writing to also knew.  Constantinople was a mystery and it still is for most. It had seven hills.