The AI in Civilization VI can be quite annoying which sometimes ruin the game. It has problems like not being able to capture a city once walls were built. Another problem is the bad production of AI. Solutions for these involves removing the city defenses and making a slight increase in production.
How To Disable Walls And City Defenses
A steam user named Quevik noticed the AT crews didn't attack the cities when Bismarck sent the crew to capture a city defended by a wall. The five AT crews just stood there and died, which he thought of a solution for. He found out this can be solved by disabling the wall.
Navigate to your Steam directory. Its default location should be under C:\Program Files (x86)\Steam. Now go to steamapps\common\sid meier's civilization VI\base\assets\gameplay\data. Next thing you do is search for the files names "Buildings" and "Civics". Be sure to make backups as you are about to make changes to the codes.
Open the file "Buildings" and look for the code ( OuterDefenseHitPoints="50" OuterDefenseStrength="2" ). This text is found in three places of the file. Change both "50" and "2" to "0" in all of the three. Save the file and close it.
In the file "Civics", edit it by first searching for the text ( DefenseValue ). Once you found it, there is a number 200 under that line. Change it to 0. The original lines that say:
Should now be:
The modifications you just made will cause the walls and city defenses to be nullified. This will make easier for the AI to capture cities. Note that this will, however, remove your cities' auto attack ability, therefore, you must defend it with troops.
How To Increase AI Production
Another problem Quevik found is the horrible production in the game. Civilizations finish their building before replacing the troops they lose in a war. His solution for this is making an overall 20% increase in production allowing both AI and player to build more stuff.
Navigate to the same directory - C:\Program Files (x86)\Steam\ steamapps\common\sid meier's civilization VI\base\assets\gameplay\data and look for the file named "Terrains." Again, be sure to back it up. Now scroll all the way to the bottom until you find the lines:
Now increase all the numbers by 1 in these lines. This will cause an overall increase in terms of production in the game. You can always replace these files with the original backups in case you want to play with the default settings. You can also turn on multiplayer for Civ 6 with this guide.