Some people have a hard time forgetting old games they liked. That's why there's a LOTR mod for Age of Empires II. That's why Age of Empires II HD gets a paid Steam release of the "Forgotten Empires" expansion pack, which previously was just a mod for AoEII. Among other things, it includdes 5 new civilizations:

Italians - Set sail to Venice and take the role as general in one of the Italian republics that emerged from the chaos after the collapse of the Roman Empire!

Indians - Put vast armies under your command, comprised of countless Camels and powerful Elephants.

Slavs – Even after the dissolution of the Mongolian Golden Horde, these icy planes of Eastern Europe still echo under the thundering hooves and countless boots of your soldiers.

Magyars - Lead the mighty Black Army over the Hungarian plains and command the fiercest cavalry forces that Europe has ever witnessed in the Middle Ages

Incas - Lead your armies along the shores of Lake Titicaca, defend your wealth and heritage from the invading Conquistadors and erect mighty structures to withstand the test of time.

And what's the biggest news about it all today? It's going out on November 7th. So, Age of Empires II HD owners, you're getting an add-on... after a ten year gap. Not many people outside MMORPGs can say that.