C30 The Soldier Zhang San.

Territory Alert: "You have spent 300 spirit coins. The White-robed Ghost Troop has been upgraded to Level 2."

Territory Alert: "You have spent 600 spirit coins. The White-robed Ghost Troop has advanced to Level 3."

Territory Alert: "You have spent 900 spirit coins. The White-robed Ghost Troop has reached Level 4."

Upgrading the level of a building undoubtedly brings numerous advantages