In contrast to other RTS games, Age of Empires featured only the same units for all civilizations, with some exceptions and bonusses for each team. Later, the Age of Empires Gold Edition came available, which included both games. The game later featured an expansion, with a couple of new units and scenario’s. The AI of the computer players where, for that time, very advanced. Age of Empires was made in 1997 and the first game Microsoft produced (with Ensemble Studios) that became a big hit.