Assault

it’s logical that there are few objects suitable for this idea, because the game already has a ready-made city. But even in the third game, you can come up with something. Instead of walls, you can add border gates without a tent on the map, or a garrison with a million Azure Dragons – it’s a bit of a perversion, but it looks like walls and fulfills the idea. Besides, half of the custom maps are just such perversions.