Civilization 6 will soon be getting a Civilization and Scenario Pack, though the release date and pricing haven't been revealed just yet. What the developers did reveal, however, is two of the nations that will comprise the "civilization" part of the pack: Persia, and the newly revealed Macedon.
I must admit that the announcement of Macedon comes as a bit of a surprise given how over-represented Hellenic nations are in Civilization 6, but since Alexander the Great conquered Persia I suppose it makes sense. As you might imagine, Macedon will be a civilization primarily focused around prolonged warfare and conquest. In order to ensure this doesn't leave you weak and exposed each city you conquer will give you a variety of bonuses, while Macedon's passive ability helps reduce war weariness so that you can stay at war for much longer.
The Hypaspist, a Swordsman replacement unit
As far as units are concerned, the first and most important one you'll be able to recruit is the Hypaspist, a Swordsman replacement that gets extra combat strength when besieging districts. The second and final unique unit is the Hetairoi, a Horseman replacement that brings with it speed, endurance, and incredible 'firepower' in one single package. And as an added bonus, Macedon's unique building Basilikoi Paides will yield science each time you recruit a combat unit, thus making sure you never fall behind despite the constant warfare.
You can check out what Macedon looks like in-game via the recently posted teaser trailer right below. Much like the one for Persia it doesn't really go in-depth about any of the units or upgrades, but it should at least give you an idea of what Macedon's playstyle is going to be like. Anyway, have a look: