Events concerning Cerberus during the war are collected here.
June 15: Cerberus Coup
A desperate Councillor Udina, representative of the human Systems Alliance to the Citadel Council, contacted Cerberus to coordinate what was intended to be a bloodless takeover of the Citadel, in which he would force the other councilors to grant him emergency powers so that he could command the Citadel Fleet. He would then direct the fleet to liberate his homeworld, Earth, which was firmly under Reaper control.
The plan fell apart early when Executor Pallin and the salarian councillor caught wind of it. In defense of the plot, the Illusive Man dispatched his top assassins, commanded by Kai Leng, to kill them. Udina had little choice but to support the assassins with an armed force sufficient to hold the Citadel. Captured confidantes indicated that Udina and Leng’s alliance was relatively fragile: Udina may have planned to turn on Cerberus once the fleet was his to command, and Leng departed when he calculated that Udina wouldn’t succeed.
The Normandy received a transmission from an old friend of Shepard's, informing them that the station was under attack.
Due to the nature of the failed insurgency, Councilors Valern, Sparatus, Tevos and hastily-sworn in Osoba were unavailable for comment. However, each of their embassies urged Council Space members not to panic in the face of the attempted coup.
In a prepared statement, Paquis Zhelvan of the Hierarchy’s Office of Public Information reminded members of Citadel Space that,
“While this attack is appalling, using our resources on counterattacks against Cerberus will not solve the larger, much more pressing problem of the Reapers. We understand that a large number of turian citizens, both civilians and members of C-SEC, were killed today. With our forces engaging the Reapers both on Palaven and in other theatres, this is a terrible blow, but we must remain on-target and work together if we are to survive.”
The Offices of the Salarian and Asari Council were similarly cautionary. In a joint statement by Xevan Chiota and Malkis Oarian, Press Secretaries for Councilors Valern and Tevos, the Citadel Council stated that,
“We have seen many atrocities during this war and, while Cerberus’ actions are despicable, we must work together to defeat the Reapers. Now, more than ever, we need soldiers to help defend the many colonies throughout the galaxy who face imminent attack by Reaper forces.”
To quote Commander Mark Wallace (N7):
"The ramifications of the assault are huge, most of them good. Dominic Osoba is better than Udina, the asari and salarians are providing a token amount of military aid while their prominant members are seriously considering furthur aid and more people care about the fact that there are docking bays full of refugees and that we are losing contact with entire systems. In the grand scheme of things, the attack on the Citadel will probably do more to help us than hurt us in the war".
Public sentiment regarding Cerberus, already hostile, became even more vehemently opposed. Human casualties, both civilian and C-Sec, as well as Shepard’s decisive role in defeating the attempted coup, lessened the degree to which this hostility spread to humans in general, and species-based reprisals were sporadic and, compared to the state of tensions generally, minor.
The Council created the Citadel Defense Force to support Shepard in the war against the Reapers. The CDF included ships and soldiers from every Council race. Complements from a few species without official membership status also quietly joined. After the attempted coup, no offer of assistance was being turned away by the Council and its advisors.
July 25: Sanctuary
Upon arriving at the facility, Shepard and her squad discovered signs of battle between Cerberus and Reaper forces, a surprising discovery given Cerberus’ collaboration with the Reapers. Investigating the camp, Shepard found evidence that the ‘refugee camp’ was in truth a Cerberus laboratory run by Henry Lawson, working for the Illusive Man. Deeper in the facility, they discovered that the refugees were being experimented on and ultimately turned into husks, in order to further Cerberus’ research into indoctrination. A further bombshell was brought to light: a signal being broadcast from a tower within the facility, using Cerberus research, had allowed Cerberus the ability to control the husks created in their experiments. Lawson had been working on the Illusive Man’s orders to find a way to transfer this process to the Reapers themselves before the facility had come under attack, the Reapers seeking to destroy any potential weakness that could be used against them.
Alliance specialists were soon sifting through the remains of Sanctuary, decrying ‘unspeakable atrocities’ carried out by Cerberus. “The people fleeing to Sanctuary were drawn by promises of security in a war-torn galaxy,” said Admiral Hackett in a prepared statement. “Cerberus betrayed their trust, and took advantage of refugee panic and desperation. What we’ve seen here today gives the ultimate lie to Cerberus propaganda, to their claims of being humanity’s ‘beacon of hope.’ It’s clear that no one, human or otherwise, is more than a tool for their own despicable purposes.”
Human Councilor Dominic Osoba issued a statement on the discovery as well, stating that,
“On behalf of all humanity, my heart breaks for the victims of these cruel charlatans. Humanity cannot truly stand together against the Reapers unless we root out and destroy the terrorists in our midst, those who seek to undermine everything humanity stands for in the name of their foul work.”
August 1: Down With Cerberus
The Hierarchy collaborated with factions from the Terminus and the Systems Alliance in an operation to reclaim the warship Defiant - previously taken by Cerberus following the failed coup. As such, the 23rd Patrol Flotilla was assigned to wrest it back from enemy hands; spearheading a joint fleet action to take not only the frigate, but also the key Cerberus station it had been hiding in. Led by Captain Nasrin Avita, the 23rd Patrol Flotilla as well as the rest of the joint action fleet struck the station, which was fortified by its own fleet and the occupying garrison. As the initial blows were exchanged, the casualties among the coalition mounted - namely, ships from the Systems Alliance Eighth Fleet who had jumped through the Relay first. However, the tides quickly turned when Captain Avita pulled off a masterful manoeuver; executed alongside a Terminus fleet, which succeeded in sweeping Cerberus naval presence from the system and allowing the coalition opportunity to seize the advantage.
But while the Defiant was safely secured, Veratix Station was scuttled by the remaining Cerberus forces, resulting in heavy damage to the structure. Operatives from the Office of Technological Reconnaissance were dispatched to recover what they could from the station, alongside similar agents from both the Alliance and the Terminus Systems.
August 3: Further Down With Cerberus
Hackett warned that once an assault on Cerberus was launched, the Reapers would take notice; for all intents and purposes, the attack on Cerberus would be the first step in the campaign to retake Earth. Once military preparations were completed to Shepard’s satisfaction, the assault began.
Leading an armada to assault the station, Shepard, EDI and a squad were deployed to fight Cerberus forces in the base, while Hackett battled Cerberus’ fleet with the rest of the Alliance ships. The base was full of video logs, containing intel on EDI’s past, Project Lazarus, and Cerberus’ new-found obsession with exploiting Reaper tech and indoctrination, as well as interesting technology such as prototype weaponry and pieces of the Human Reaper salvaged from the Collector Base after its destruction. Eventually the team reached the Illusive Man’s personal office, and began to scour his private terminals for the location of the Prothean VI. The Illusive Man contacted Shepard by hologram, sneering that he’d already acquired the Catalyst and all he needed to control the Reapers. Again, he dismissed Shepard’s claims that he was indoctrinated and assured Shepard that the idea behind Cerberus would survive any physical damage they caused to the organisation itself.