The confrontation between the two worlds was a result of the oppression the Rhommamoolians suffered under their richer Osarian neighbors. The two planets had an orbit that brought them within a million kilometers of each other every ten years, usually resulting in a flare-up of hostilities. While the wealthy Osarians lived in relative luxury on white sandy beaches and crystal-clear lakes, the vast majority of Rhommamoolians lived in poverty as miners on their inhospitable desert world.
The Rhommamoolians were also underrepresented in the Osarian government which ruled both worlds and had suffered because of this. Though most of the miners had immigrated to Rhommamool voluntarily, many were convicts exiled from Osarian as a result of their crimes. Osarian also had a small space fleet though its technology was mainly limited to the ground.
The Yuuzhan Vong agent Nom Anor fanned the flames of war and incited religious and anti-technological feelings among the Rhommamoolians. Anor founded the fanatical Red Knights of Life and preached hatred of all forms of technology ranging from droids to landspeeders. He also called for his followers to look for "truth" in nature and the life of the universe and to resist the joining of planets in "false confederations".
The Red Knights also hated the New Republic and the Jedi. In 25 ABY, the Red Knights took control of the planet and went on a rampage destroying any form of technology. They dragged droids to the Square of Hopeful Redemption in the Rhommamool city of Redhaven, where they would cast them into a large pit and bombard them with rocks, most notable of which was C-9PO. Nom Anor formed an independent senate and a group of religious fanatics, the Red Knights of Life, to push his agenda.
Anor's call for action against Osarian led the New Republic to dispatch a Mon Calamari Star Cruiser, the Mediator, to keep the peace, while Jedi Knight Wurth Skidder arrived to take vigilante action against whichever side showed aggression. The Osarian leader, Shunta Osarian Dharrg, hired Captain Grappa and his Osarian First-Force to help defend the world.
Despite the arrival of Leia Organa Solo, Jaina Solo, Mara Jade Skywalker and C-3PO to negotiate, the situation was impossible to resolve due to the fact that Anor fully intended to use it to cause as much destruction and chaos as possible. Following her departure, whipping his followers into a holy rage, Anor arranged for the assassination of several key Rhommamoolian leaders and used it as a justification for war against Osarian.
Conferring with the other Red Knights, Nom Anor suggested a nuclear missile strike against the Osarian capital Osa-Prime. However, he was opposed by the moderate Tamaktis Breetha who feared open war between the two worlds. Unfortunately, Breetha found little support. To prevent the Mediator from intercepting the missiles and to make sure the missiles hit their targets, he and Shok Tinoktin studied the planetary courses and the positioning of the New Republic starship.
These missiles were launched from a point where the initial explosive liftoff and subsequent burn would be most difficult to detect. Having broken orbit, the missile were shut down to make them appear as little more than insignificant specks to the crew of the Mediator and then fired again, entering Osarian's atmosphere and hitting the target: Osa-Prime. By the time the Mediator and the Osarians realized it, it was already too late. The Osarians attempted to destroy the missiles by firing more missiles and sending starfighters to intercept them but to no avail and soon Osa-Prime was in flames.
When Commander Ackdool contacted Nom Anor, he took full responsibility and claimed that they were in retaliation for the assassination of several Rhommamoolian officials before cutting of contact. Later, Nom Anor and Shok Tinoktin left Rhommamool on an empty booster shell with a modified RZ-1 A-wing interceptor and nuclear fission explosives tucked inside, since they planned to detonate the shell once within the Mediator, presumably killing Nom Anor and making him a martyr for Rhommamool while they escaped on their A-wing. During this mission, they were forced to travel through a maze of starfighters and missiles. By then, large red thermonuclear blast clouds were forming over the surface of Osarian since more missiles had already been launched by Rhommamool.
When approaching the Mediator, the booster shell then opened line with the battle cruiser. At the capsule's cockpit, Nom Anor placed a villip which imitated his actions, acting as a decoy while he remotely piloted the booster shell from their A-wing. As they were conversing, they were attacked by Osarian Z-95 Headhunters. Nom Anor then offered Ackdool a promise to cease fire in return that they be protected on their way to the Mediator and escorted home to Rhommamool following the discussion. When in position, the A-wing detached from the booster shell. Nom Anor and his accomplice Tinoktin escaped on their A-wing while the booster shell crashed into the battle cruiser's lower docking bay and exploded, destroying a huge section of the lower floor of the Mediator, thus crippling it.
It was presumed that Nom Anor had been killed, making him a martyr for Rhommamool and worsening the conflict. However, he and his accomplice escaped. Following that, Nom Anor was contacted by Prefect Da'Gara who suggested that their next target be Sernpidal which would be destroyed through the Yo'gand's Core tactic which involved using a dovin basal to cause a planet to collide with one of its moons.
Later, the Red Knights of Life attacked Osarian, though they would be repelled by the Jedi-allied Iron Knights.
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