Having completed the introductory volume, I am skipping ahead in the series to the Popes of the Protestant Reformation, starting with Leo X, who confronted and eventually excommunicated Martin Luther. The first volume of Pastor's two-part history of Leo X's papacy is now available. The second should be up by the end of next week.
The new, paperback edition of the first volume is available by clicking the image below. (The cover image is different, to distinguish it from the hardcover edition.)