Water attack is to have several cities close to the water. Then send a team to attack the city. After several teams are surrounded, a prompt will pop up to launch a water attack. Moreover, the siege team must have a military commander with a fortification suitability of S before it can be launched. A surprise attack can't be launched until the computer troops enter the city you own. The success rate depends on the command of the surprise attacker and the victim. The agreement ninja group helps to improve the success rate of surprise attack. When an enemy team enters your territory, you can directly click on the surprise attack of the troops.