For those who have not Played Ace Combat X I'll do a small rundown of what the Gleipnir is. It's a large flying fortress. Its weapon systems are some SAMs (Surface to Air Missiles) and some Anti-Air Guns, Shock Wave Ballistic Missile or SWBM are used for destroying Air targets at longer range, and a Shock Cannon on its belly. It is powered by Particle accelerator technology. It also has a optical camouflage systems.

To the actual reason you are here: In this story when Gryphus One was able to destroy the Shock Cannon it created an Rift causing the Gleipnir to fall into it. When they awake they are in a world that is at War like them. Nightmare Moon trying to bring on eternal darkness that would be nice for the Gleipnirs crew because the worlds a bit to bright but besides that. In the Griffin Kingdom, Barbarian Griffins try to raid a small village that the Gleipnir is close to so they get involved an launch a SWBM vaporizing the raiders before they even got close. Now the Lunar Republic and Solar Empire are racing to get control over this New Super Weapon.