This mission has no corresponding operation page since it is not considered part of Strangereal canon.
For the location, see Atmos Ring (structure).

Atmos Ring is Mission 12B in Ace Combat X: Skies of Deception.


  1. No change in mission parameters (Santa Elva > Striking Point > A Diversion > In Pursuit II > Break In)
  2. Increased number of enhanced cannons (Santa Elva > Striking Point > A Diversion > In Pursuit II)
  3. Aircraft: limited special weapons (Santa Elva > Blitz > In Pursuit I > Break In)
  4. Increased number of enhanced cannons + Aircraft: limited special weapons (Santa Elva > Blitz > In Pursuit I)


Our mission is the liberation of Griswall. I'll explain the details. Griswall is protected by the Atmos Ring powered Meson Cannon. Our troops will not be able to approach the city because of the MBSRs (Meson Beam Stabilizing Regulator), brought in from Monte Breeze. Our only hope is to send a small squadron of fighters in for a surprise attack, and take out the cannon. Fortunately, the enemy has put all of their faith in the cannon, and has yet to deploy ground troops. Destroy the Meson Cannon and the fighters protecting it, and the city is ours. The capitol's liberation is finally within our grasp. Sir, please decide the course of action.

Variations 3, 4

"Be aware, supplies from Santa Elva have dried up and special weapons are scarce. Use special weapons with caution as their number will be less than the standard amount."


The mission's main objective is to destroy all targets. There are several SAMs protecting the Meson cannons, and several fighters providing air support. In addition, reinforcements will arrive after several targets are destroyed.

Enemy Lists

Standard Units

Unit Points Count Notes
Icon-AirTGT.svg Gripen C 640 2
Icon-AirTGT.svg F/A-18E 520 2 [note 1]
Icon-AirTGT.svg F-16XL 480 2 [note 2]
Icon-AirTGT.svg YF-23A 700 2 [note 2]
Icon-AirEnemy.svg AH-64 100 2 [note 3]
Icon-GroundTGT.svg Meson C 750 4 [note 4]
Icon-GroundTGT.svg M.B.S.R. 1500 4
Icon-GroundTGT.svg M.B.S.R. 1500 4 [note 5]
Icon-GroundEnemy.svg SAM 180 3
Icon-GroundEnemy.svg AA GUN 150 4 [note 6]

Special Units

Unit Points Minimum
Icon-AirEnemy.svg Gripen C "Riot" 1280 Normal [note 7]
Icon-AirEnemy.svg ★CH-47 100 Easy [note 8]


Earning an S-Rank requires clearing the mission under 7 minutes and 30 seconds.[1]


Griswall's been liberated! With the lost of their central command, Leasath forces have begun to pull out of Aurelia. The streets of Griswall are overflowing with citizens celebrating the defeat of the Leasath oppressors. Even soldiers have joined in the celebration. We've done it sir!


  1. Appears after two target aircraft are shot down.
  2. 2.0 2.1 Appears after four target aircraft are shot down.
  3. Appears after three ground targets are destroyed.
  4. Only appears in variations A and C.
  5. Only appears in variations B and D.
  6. Appears after both AH-64s are shot down.
  7. Appears to the southeast after four target aircraft are shot down with 4+ ground targets remaining.
  8. Appears after 12 aircraft are shot down.


  1. Ace Combat X: Skies of Deception - The Complete Guide, pages 134-137.