The Feudal age is the third age, to reach it you need: 2500 glory, 200 spirituality, and a hero of level 20. In this age, you can get other sorts of heroes from the tavern. The following buildings can be constructed in the Feudal age:

Civic center: For research to enhance heroes, missionaries and merchants.Edit
Stables: For recruiting mounted units.Edit
Trade post: For dispatch of merchants to gain gold.Edit
And these units can be trained in the Feudal age:Edit
Cavalry: Mounted units with a high attack value but a low defence. They are very mobile.Edit
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