You might see a Defend City choice show up at the lower part of the screen when visiting your city. This shows that you are at present being assaulted! You will want to partake in the battle, assuming that you select Defend City. You'll have the option to safeguard your city continuously by conveying hoplites and toxophilite to battle off attacking divine beings. It's discretionary to protect your city face to face, yet it's gigantic assistance to your city's protections!