Orc

Orcs are a major non-human race. In most scenarios, they will frequently start as a Nation in Shadow, meaning it will be easy for the Old One to recruit from their number.

Race
Lesser Race

"Cursed by the primal blood that runs through their veins to a life of constant warfare and strife, Orcs are a constant thread to the civilized peoples."

We do not yet know what the baseline Orc is like.

Culture
We do not know what sort of culture the Orcs usually have. It will likely be warlike and savage.

Orcs are Patriarchal by default, rarely producing female armies or units.

Orcs live anywhere so it's hard to force them to migrate - they even live inside the gorges left from earthquakes or in "blasted lands" of constant storms. It's also somewhat hard to drive orcs because they can just collapse back into their tribal configuration, leaving you to take over the POI while they exist as a lair modifier on the POI. If you spend the time to roust them out THEN they will finally move along. (it's much easier with human tribes to passively encourage some migration)

Government
Orcs are either Clans or Hordes - and there is a fair amount of variety inside those two to allow for different types.

A Horde is ruled by a single strong ruler that has brought together disparate bands of orcs. Hordes easily integrate random orc tribes and can mobilize large forces at will, but pivot entirely around the personal abilities of their leader - take down the leader and the entire Horde may collapse. Hordes are not very good at controlling multiple POIs, and they'll often migrate from POI to POI with their population to maintain order in new areas.

Clans have much more stability, with tradition and order benefits derived from a much stronger culture than a horde. Rulers can be an individual or a council, and you'll find a much more traditional approach to gameplay with a clan than a Horde.

Regressing a civilized nation to a primitive state would never occur in a regular game without support. A lot of what we've done is to allow things to occur but make them essentially impossible during a game's normal timeframe so that they can be manipulated by powers/abilities. In addition, with Endless Mode you can pass enough time to fully eradicate a culture and render it's descendants into a primitive form, though you would need to have some impressive patience for that to happen.

Humans have the greatest variety of responses to stimulus inside the simulation - so a human civilization being reduced to a tribal warlike state is possible (as are other, darker, paths for a beleaguered nation to follow). Orcs can have their culture and relations altered by trade, to the point where they can become allies of human nations though it is much more difficult to accomplish. They will never make the leap to a democracy however, at best retaining their government but in a more civilized structure.

Classes
Given the Kickstarter Races each had two unique classes, it is likely the Orcs will have at least that many.

Agents
The Hordemaster is available from the moment you suborn an Orc tribe. He allows quick recruitment of troops to form an Orcish Horde.

Old Ones
Karth has a deep connection to the Orcs.

Military Units
We know basic Orc units are supposed to be weak and easily slaughtered. Karth's early ability Bloodlust ensures that enemies will always take damage, even when they greatly outmatch an opposing Orc unit.

Shadar Orcs are from the Age of Domination (if you choose orcs as your servants during the scenario setup) and they are well trained and disciplined, much more civilized. Choosing orcs as your servants turns a few of the orc tribes into Shadar Orc Cults, Most orcs have become a more formal nation-state ruled by a powerful orc king. But the Shader orcs are still ruled by the disempowered religious caste that holds true to your name (and reigns through fear) and have laid low awaiting your return. The normal orc kingdom will flock to your banner and give you access to some unique minions, but the Shader orcs give you elite units but are much more difficult to return to the fold (you can't simply duel their chieftain like you can with a normal orc kingdom). A downside to the Shadar orcs is that the cult keeps your name alive, so heroes performing quests in their vicinity will be able to gain not just Ancient clues but also clues to your Old One identity which can be devastating.