The Arm of Orion, a proxy rebel group founded by US Imperial defectors, was funded and tasked by the mysterious group known as the Orion's Spear to overthrow the United States Empire as vengeance for perceived betrayals against them.
The Arm's first step was to quickly and decisively invade the Empire's outer colonies and shut down their Titan Array, completely disabling planetary communications, leaving the besieged planet unable to warn others. The Arm then blockaded the planet to stop any attempts at escape, as well as to prevent aid from the United States Imperial Forces (USIF), the powerful military of the Empire. Finally, the Arm scoured the planet for any technology they could reverse engineer for their own use.
The US Empire Strikes BackEdit
The Liberation of New MadridEdit
Once word reached the USIF Military Headquarters stationed in the Pentagon Fortress on Earth, a Battlefleet was dispatched to deal with the growing threat. After a few hours of travel in a "Singularity Jump," the fleet reached the fringe planet of New Madrid. The Arm immediately started bombarding the fleet with their Orbital Defense Cannons. Taken aback by the Arm's well-prepared naval defenses, the 8th Armored Infantry Division (or Section 8) quickly hot-dropped the 1st Recon Platoon onto the planet's surface to neutralize the generators powering the anti-orbital cannons.
After the destruction of the cannons, the 8th Armored Infantry Division's ships were able to land more troops and eventually gain a foothold on the planet. General Barrett Stone, commander of Section 8, then sent 1st Recon to recover intelligence from the crash site of the USIS Utah, shot down during the initial stages of the invasion. Shortly after the recovery of the intel, 1st Recon witnessed the first launching of the Arm's nuclear missile defense, and was ordered to take out the facility before more US Imperial units were obliterated. In a few hours, the launch facility was shut down and captured, allowing Section 8's forces to further advance against the Arm rebels.
While the support fleet slowly broke the Arm's defenses through a protracted orbital siege, 1st Recon was again sent on a vital mission: to recapture Oasis City, key to New Madrid's liberation. Two assault convoys with a complement of two tanks were sent to breach the outer defenses and take control of the city's perimeter. After successfully seizing the Oasis City perimeter, the bulk of the 8th Armored forces broke through to retake the city itself. It took another week of brutal combat, but the Arm eventually withdrew from New Madrid altogether to fortify its remaining captured colonies.
The Liberation of AtlasEdit
The 8th Armored Division Battlefleet then held high orbit over the planet Atlas, having discovered an Arm presence there. The 1st Recon Platoon was then covertly deployed to shut down the planet's orbital defense grid while the fleet stayed out of planetary gun range, Section 8 having learned from their near-catastrophe at the outset of New Madrid's invasion. After the planetary guns were disabled, the 8th Armored Infantry Division then landed its forces in earnest, to begin the liberation of Atlas.
Days later, the 1st Recon Platoon was ordered to captured the Arm-controlled Titan Array, a massive planetary antenna network enabling effective Faster-than-Light (FTL) communication. The Titan Array was soon captured, allowing the Section 8 Battlefleet to intercept Arm communications, and set a fitting trap for the Arm. The Battlefleet's AI network nicknamed 'Mother' then fed false information to the Arm Fleet, luring the Arm ships into a US Imperial Navy ambush carried out by the Columbia Battlegroup. Section 8's humiliation on New Madrid had been avenged.
Section 8 then sent 1st Recon Platoon to destroy a major Arm weapons and vehicles manufacturing complex in a hidden location on Atlas. The complex was soon destroyed, crippling the Arm's very ability to wage war. As the battle on Atlas dragged on, the 8th Armored Infantry Divsion was finally reinforced with the 3rd Armored Infantry Division, wearing the Arm's beleaguered forces even further. As more and more of the planet was recaptured by the combined US Imperial forces, Section 8 intercepted intelligence confirming the location of Commander Soren, rogue Section 8 officer and leader of the Arm resistance, and that he was preparing to evacuate the planet.
The Arm's DownfallEdit
The 8th Armored Infantry Division's 1st and 3rd Recon Platoons were immediately sent to Soren's general location to kill the rogue Commander before he could escape, and put an end to the Arm Rebellion once and for all. After fighting their way through fierce resistance to the planet's Sky Hook spaceport, 1st and 3rd Recon Platoons cornered Commander Soren.
However, Soren would not surrender so easily, attempting to fight his way out with a modified version of the Silverback Heavy Armor alongside his elite bodyguard unit, the Orion's Spear. Eventually, 1st Lieutenant Alexander Corde, leader of the 1st Recon Platoon, was able to kill Commander Soren by jumping onto the back of the heavy armor, shooting off the head, and forcing a grenade down through the Armor's "body" inside the cockpit where Soren himself lay, avoiding the grenade's explosion with his jetpack.
Soren's death left the few remaining Arm of Orion forces without leadership and in disarray. They began to retreat further to the galactic core, closely trailed by the Section 8 Battlefleet. The Arm left scattered ships and ruined bases to defend against the onslaught of the mighty US Imperial Forces. These paltry defenses quickly crumbled, with all remaining Arm members being killed or taken prisoner.
Though the Arm had been dealt a fatal blow from which it would never recover, this caused controversy amongst the US Empire as whole, which had previously underestimated the Arm's capabilities. The level of damage the Arm had inflicted on the USIF, especially the legendary 8th Armored Infantry Division, shocked many who once thought that the feared Armored Infantry were nigh-unstoppable in the entire galaxy. In addition, many wondered where the Arm could have obtained the level of military technology that they did in order to even challenge the USIF directly. This storm of controversy caused many USIF intelligence officers to resign their posts because of the damage such an intelligence failure had caused to the US Imperial Military's reputation.
Even worse, the Arm's failure was clearly evident to their sponsors, the Orion's Spear. This turn of events is what would eventually force the hand of this mysterious and dangerous organization, and they would confront and destroy the forces of the United States Empire themselves. Thus, the events of the Spear Crisis were set.