Last Line of Defense is a campaign mission in Ace Combat X: Skies of Deception. This mission is only available as long as the player does not play Rolling Thunder or The Midnight Sun first; playing either mission results in the Miller Unit retaking Port Patterson and sending supplies from the port to Santa Elva via Kingshill, which unlocks the missions Captive City and False Target. The player must defend the entrances to the tunnel from the Miller Unit.


Eugene Solano: Leasath's Miller Unit is meeting up at Kingshill. Based on the sheer strength of the enemy force, an offensive aimed at retaking Port Patterson appears imminent. A partially completed highway runs directly from Kingshill straight into the heart of Port Patterson. The enemy intends to use this highway to swiftly spearhead its way through our defenses. Their ground forces must be destroyed if Port Patterson is to remain ours. Our soldiers are in a precarious position. If they are attacked now, they will have no choice but to abandoned the port. One more thing. On the highway leading to Port Patterson, there is a tunnel. If an enemy tank makes it to the tunnel, it will be beyond the reach of any air assault. If even one enemy tank enters the tunnel, our mission will fail. Please make sure this doesn't happen.


In this mission, the player must ensure that no enemy unit reaches the tunnels; if any break through, the mission fails. In addition, there are several enemy aircraft protecting the vehicles.

The mission ends when all targets are destroyed.

Enemy Lists

Standard Units

Unit Points Count Notes
Icon-GroundTGT.svg Launcher 120 1
Icon-GroundTGT.svg Vehicle 100 2
Icon-GroundTGT.svg Launcher 120 1 [note 1]
Icon-GroundTGT.svg Vehicle 100 1 [note 1]
Icon-GroundTGT.svg AA GUN 150 1 [note 1]
Icon-GroundTGT.svg Launcher 120 1 [note 2]
Icon-GroundTGT.svg Vehicle 100 2 [note 2]
Icon-GroundTGT.svg Tank 200 1 [note 3]
Icon-GroundTGT.svg Launcher 120 1 [note 3]
Icon-GroundTGT.svg Vehicle 100 1 [note 3]
Icon-GroundTGT.svg SAM 180 1 [note 4]
Icon-GroundTGT.svg Launcher 120 1 [note 4]
Icon-GroundTGT.svg Vehicle 100 3 [note 4]
Icon-GroundTGT.svg AA GUN 150 1 [note 4]
Icon-GroundTGT.svg Tank 200 1 [note 5]
Icon-GroundTGT.svg Vehicle 100 1 [note 5]
Icon-AirEnemy.svg A-6E Intruder 100 1
Icon-AirEnemy.svg F-1 260 3 [note 6]
Icon-AirEnemy.svg A-10A 400 2 [note 7]
Icon-AirEnemy.svg JA 37 Viggen 300 2 [note 8]
Icon-AirEnemy.svg MiG-21-93 Fishbed 440 2 [note 9]
Icon-AirEnemy.svg JA 37 Viggen 300 2 [note 10]

Special Units

Unit Points Minimum
Icon-GroundEnemy.svg Vehicle 100 Easy Star Unit. Unlocks Extra Airbrake when destroyed. [note 11]
Icon-AirEnemy.svg MiG-21-93 Fishbed "Rose" 880 Normal [note 12]


Achieving an S-Rank on this mission requires earning 6,500 points.[1] If the player destroys all shoots down all enemies except the ace, they will earn exactly 6,500 points.


Eugene Solano: We've succeeded in preventing the Miller Unit from invading Port Patterson. Leasath forces are in retreat. Let's hope they've learned their lesson and think twice before trying to take Port Patterson again.


  1. 1.0 1.1 1.2 Appears after the first group of targets is destroyed.
  2. 2.0 2.1 Appears after the second group of targets is destroyed.
  3. 3.0 3.1 3.2 Appears when two targets from the third group are destroyed.
  4. 4.0 4.1 4.2 4.3 Appears when all targets from the fourth group are destroyed.
  5. 5.0 5.1 Appears when any target from the fifth group are destroyed.
  6. Appears after any two targets are destroyed.
  7. Appears as reinforcements after all but one of the previous aircraft has been shot down.
  8. Appears as reinforcements after all but one of the previous aircraft have been shot down.
  9. Appears as reinforcements after all but one of the previous aircraft have been shot down.
  10. Appears as reinforcements after all but one of the previous aircraft have been shot down.
  11. Spawns at the end of the middle road after ten targets are destroyed.
  12. Appears to the North when ten targets are destroyed after all aircraft are shot down.


  1. Ace Combat X: Skies of Deception - The Complete Guide, pages 062-065.