Thanks to your contact in Radiata, you can make plans to infiltrate Castrum Abania and ensure that the cannon is not repaired.
This quest is available if you have completed the quest Where Courage Endures, and have reached level 69.
Starting the Quest
Talk to Alphinaud in The Peaks to begin the quest.
Search for Imperial Patrols
Go east to the quest icon on the map and check on the purple Destination. Defeat the Imperial Hoplomachus and the Imperial Predator that attack.
Go east and check on the purple Destination. Defeat the Imperial Laquearius and the Imperial Canis Pugnax that attack.
Speak with Stark Woad
Go southeast to the quest icon on the map and talk to Stark Woad.
Lie in Wait
Go east and check on the purple Destination. Defeat the Imperial Hoplomachus and the Imperial Rearguard that attack.
Go southeast and check on the sparkling Destination. There will be a cutscene.
Use the Duty Finder or Duty Support to enter Castrum Abania. Please see the Castrum Abania Guide for a walkthrough.
After you complete the duty in Castrum Abania and exit the area, there will be a cutscene. This one is important, so it is recommended to watch it either now or via the Unending Journey in an inn room.
Speak with Lyse
Talk to Lyse to complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Raubahn to accept the next quest: Raubahn's Invitation. There will be a cutscene.