I've played open world games like the Witcher 3, or Assassin's Creed Odissey; and damn they're impressive games. Assassin's creed in particular was really amazing, you could wander through ancient Greece and just enjoy the sights, visit the cities.

With the kind of things demoed here it will be even more amazing.

But the games feel somehow lifeless, as if you're the only one really living in there. Sure there are some NPCs, but they are all reactive, not active. You can roam the countryside for a while and come back to civilization, nothing will have changed, except maybe the town will be governed by blue instead of red.

There's some premises, on Odissey, you have some patrols for both sides moving around, and if they encounter each other they start fighting. But that's small scale, and partly scripted at that, there will always be the same patrols going through the same paths.

What's missing is that you cannot walk on a battle in progress unless it is in the story. You won't see a city patching up its walls after a siege, merchants running a real economy, people going on with their lives in general. But meaningfully, not just walking around the town and going back to their house at night.

I assume it's really difficult though. First technically, it's a lot of CPU power. And a lot of work to create AI that meaningfully impact the world.

Then it's how to design a game in a world you cannot really predict. It could be purely open box, a la mount and blade, but I think it could be more, with an underlying story line that would adapt to the changing world.

Of course you don't need to do everything at once. In this case, simply having the 2 armies stateful (e.g. a set number of troops with some replenishments, but not always the same soldiers in the places), with troops moving across the countryside, and 2 AIs vying for power across the land would be fantastic