This page contains information that is by its nature a spoiler. If you do not wish to know the secrets of the Golden Branch Sector, please turn back.
The September Incident was a multisided confrontation involving Rigour, the Minerva Strategic Alliance, Voice, Superintendent Twelfth and the Chime that primarily took place over Mode City on the planet Septemeber.
The Incident occurred due to happenstance as multiple organizations mobilized to the planet September for different reasons and ended up coming into conflict.
September Superintendent Twelfth utilized Voice to lure the ancient Divine Rigour to September in hopes of using Voice's ability to manipulate Divines to control it. Conversely, Rigour hoped to gain control of Voice and use it to spread its own influence. When Rigour arrived on September it crashed into the planet while Voice attempted to keep it buried; however, Rigour's Candidate was able to eventually free the Divine.
Leading up this incident, the Chime had run afoul of the Righteous Vanguard and set out from Counterweight to September in hopes of securing information or equipment that could be used against Righteousness and Ibex. While leaving Counterweight, the Chime were opposed by Jerboa and his Divine Detachment. The battle with Detachment awoke Liberty and Discovery, who had been dormant inside of AuDy, and ended with Jerboa ejected into space and Detachment captured and brought aboard the Kingdom Come.
Finally, due to the unrest caused by the rebellion of Petrichor Automedia, the Styger twins sent an asset to investigate September further, and, as the situation deteriorated, mobilized the Minerva Strategic Alliance's corporate conglomerate fleet to secure the September Institute.
Upon arriving in the September System, AuDy contacted Ibex in an attempt to parley with him. During the negotiation, the presence of Rigour was felt by Liberty, Discovery and Righteousness. With the realization of the threat facing the Golden Branch, Ibex offered to hire the Chime for two important tasks: to rescue Maryland September and investigate Rigour in hopes of determining a way to defeat the Divine.
The Chime eventually tracked down Maryland September, who refused to leave the planet; however, in the process they compromised Paisley's safe house, causing it to be raided and Paisley to suffer a point blank range shot to the head, leaving him in a vegetative state. He was brought to a hospital by Aria while the rest of the Chime continued to investigate Rigour.
While investigating Maryland's safehouse Cassander discovered the ancient Apostolosian Colossus Apokine. The Apokine sensed that Cassander was a scion of House Pelagios and reactivated in their presence, linking with the minds of citizens of the Golden Branch Demarchy and in the process sending out a signal of immense power. At the same time, Paisley's body, piloted by a backup program in his cybernetics, tracked down and destroyed Superintendent Twelfth, freeing Voice from his control.
Sensing something new in the Apokine, Rigour set itself into motion, rising up out of the planet in an attempt to secure Voice. The Minerva Strategic Alliance fleet attacked this new threat, but only proved to be a distraction. The Apokine proved more effective against it, channeling the positive energy of the Demarchy into a massive blast that seriously damaged the titanic Divine. Unfortunately, the feedback from Voice seriously injured Cassander and Rigour activated nanomachines to begin repairing the damage it suffered. At this point Mako Trig infiltrated Rigour and used his Stratus abilities to hamper the Divine's attempt to heal itself, while Aria arrived in the Regent's Brilliance and engaged the colossal threat.
Despite these heroic efforts, Rigour began regaining the upper hand; therefore, Liberty and Discovery enlisted the aid of Detachment and Voice to create a massive wormhole, enabling them to ensnare Rigour and trap it outside of space and time, giving the Golden Branch a reprieve to prepare for its return. The smaller Divines were successful, sending Rigour, themselves, and all of Mode City into an extradimensional space. Only the Chime, Paisley, Lazer Ted, and Maxine Ming escaped this fate.