Need plans for growing a city and upgrading option and stronger enemies for next levels, maybe some story and tactics, strategy. As some wrote earlier: to win most levels, a flood of archers is enough.
Well it's very easy to win. Actually it's just money problem. Give gift and demand to join to empire. Repeat several times. Then build coliseum on new territory. This is all. To solve problem with infinity army just refresh after save.
 "Army Test"){kind=icon}
 "Imperator - For Rome!"){kind=icon}