As soon as you leave for the level of civilization, create 2 types of ground-based equipment (for example, No. 1 – the most fast as possible, and No. 2 is the most powerful as possible). Build a lot of the first type technique and send it all to the enemy city (not to attack, but simply welcome closer), then go to the menu of the city of your capital and change the type of equipment on the second. We see that the whole army miraculously transformed from fast to powerful! We begin to attack the city, capture it, we again switch the type of technology in the capital, and we again have mobile troops! As a result, we have a very fast and very combat army.