Three other big things you need to know about walls: First and probably most importantly, walls don’t regenerate health on their own. But, as the walls wear down, your artillery will start doing damage to the city’s health as well, and your units will have more of an opening.
You need siege units to damage city walls-catapults, the industrial-era bombards, artillery and rocket artillery all do full damage to walls. Normal units only do 15% of their normal damage to city walls and don’t make a dent in the city itself ranged units only do half damage. Walls add a separate blue health bar to each city, and here’s the key: Regular units can’t do much damage to cities that have walls. The key to conquering and sieging cities in Civ 6 is understanding how walls work.
But any city more advanced than that will decimate your units if you aren’t properly prepared. Taking over a city without walls or encampments is basically the same as it used to be throw your units against it for a while until it falls. Wartime city mechanics in Civilization 6 are derived from those in Civ V, but expand on them dramatically-in a way that makes cities much harder to conquer if you don’t know what you’re doing.
