Each civilization in "Age of Empires: Rome Resurrected" has its own passive camp buff, which can increase their attributes in some areas. Among them, the Greek Civilization Academy has a special passive BUFF, which can increase their training speed by 30% and reduce the cost by 20%. This naturally makes them a very aggressive faction.
What is the special role of the Roman Renaissance Academy of Greek Civilization in the Imperial Age
The Greek civilization has a passive buff to their academy units that increases their training speed by 30% and reduces their cost by 20%.
This naturally makes them a very aggressive faction, as they can choose to charge early in the game or overwhelm enemies later in the game.
Think of the Goths in AoE II. This usually means that the faction with the stronger civilization bonuses (if we ignore player skills and micro factors) will win with a specific advantage, as attribute advantages will start to become more and more important.