Tanks

Tanks are the strongest general-purpose unit, powerful on both attack and defense. A tank is worth three troopers on its own. With a finished HeadQuarters it is worth five, on both attack and defense.

They cost a lot to buy but little to keep. A tank army is expensive to build and cheap to maintain, so over a long game tanks are the most efficient force.

High military morale also makes your tanks more effective, so keep it up.

Grow your economy first, and then turn your gold into tanks for a force that wins both attacks and defenses.