Grievance

Basic Information
Grievance means your people in your city are not happy, it's a setting connected to Happiness and Tax Rate.

Grievance Formula
Normally the Grievance value is 0. Unless something happened to your city and army.

What affect Grievance
The following factors affect Grievance as well:

Appease
Relive Famine : It consumes 13500 Grain and it will +5 Happiness and -15 Grievance;

Pray for Blessings : It consumes 13500 Gold, +20 Happiness, -5 Grievance.

Battle
If your city get attacked by the other players and they win, Grievance will increase.

Tips
Your Grievance will increase when you get plundered or conquered. But if you have been plundered for 5 times, your Grievance will not grow with any more plundering.