Evony Theory Crafting
Have you ever wondered why your army just sits there while your city is gets attacked and plundered on resources?
To get them off their lazy asses and fight, click your Rally Spot and check the "Open gate to fight" box!
Good troops to leave behind are the Cataphracts. These guys in large numbers can take out ballistae and catapults before they can take out your archer towers and immediately following the onslaught from your defensive trebuchet.