Concentrating on the late medieval period, Age of Chivalry: Hegemony replaces or significantly alters each of the civilizations in the original game, while adding a number of new ones, allowing the player to control Central and Western European states. Many new units and technologies have been added and gameplay dynamics have been changed considerably in this complete overhaul of Age of Empires II.
It's been a while since the last update. I've not exactly had a lot of time to work on this, but very slowly a new architecture set is taking shape: one of two Italian sets. This set will be used by the the Papal States, Florence, and, in this instance, Milan. There will be some unique twists (each of them has its own church graphics, for instance), but this is roughly what one of their cities might look like in the 15th century.