Outposts are defensive structures that help strengthen your military during battles.
By assigning commanders to outposts, you increase your overall combat strength. The number of commanders you can assign to outposts is equal to your level, making them more effective as you progress.
However, outposts come with an upkeep cost, meaning they require a steady flow of income to maintain. Additionally, the cost of outposts increases as you build more of them.
Used correctly, outposts provide a strong advantage in both attack and defense, especially in tougher battles.