In Kingdom Maker, you can have your Nobles lead armies for multiple purposes like conquering, raiding, reinforcing, defending, mining and more!

To build an army:
  • Make sure you've trained the number of each troop type you want
  • Go to the armies tab, through your navigation bar
  • Tap "Assemble Army"
  • Choose the Noble you want to lead
  • Select the Champions to lead each Battalion
  • Fill in all the troop slots to the maximum available number
  • Add equipment to each of your battalions
Your army should now be ready, but keep in mind that through research and building upgrades, you can increase the count of maximum troops held in each battalion.
Make sure to keep your armies up to date, especially after leveling up your Keep or after unlocking new Champions that might be a better fit!