Joining a corps has several perks:
  1. Corps Help. When you upgrade a building, research a technology or heal wounded soldiers, you can call for help in your corps and get time reduction when helped by other members.
  2. Corps Store. You can buy some exclusive items here.
  3. Reinforcements. When a daunting enemy attacks you, you can ask for allies' help. They can garrison their troops in your Command Center and defend it by your side against invasion.
  4. Resource Assistance. You always need more resources in the game, and after joining a corps, you can ask for resource assistance from your allies.