Cimourdain was born long ago in the distant year of 2062 in Lyons, France, long before the formation of the Systems Alliance or any knowledge of aliens, biotics, mass relays and what wonders and horrors the galaxy might hold.

Eric was always a man that wanted more than he could get in life. A family man with a great many kids, he kept insisting on trying to get out of his simple job as a janitor - no, "sanitary engineer" as he called it. Start a band, businesses, join the reserves, all these ventures failed. Still, he had managed to save up for a comfortable retirement in the colony of Shanxi, a paradise in the stars he could enjoy his later years by the side of his beloved. Unfortunately, Enora Lasalle would very soon die with the arrival of Turians to the planet's orbit. An unassuming chunk of space debris would be hurled down by the invader turning the couple's property into ash and rubble. The only solace to the grieving widower was that her death would have been instant.

So incensed with hatred was he, Eric instantly joined the fledgling resistance against the Turians. Though very old, he was still welcomed with open arms as even Turians could tell he was elderly and thus would rarely assume that he was carrying an IED or the likes on him.

Still, eventually peace came. Changed, now furious at the entire world, the Catholic faith that the man held previously dear was suddenly detested by him as the Papacy called for reconciliation with the aliens that so recently incinerated his home. He saw himself embodied in Cimourdain, the former Priest turned radical revolutionary in the French novel "93", from which he derived the name under which he contacted Cerberus as the organization published its manifesto.

Older than he already was at the time of the contact war, the young organization of Cerberus saw little use in the man. Quite cynically, when they at last relented and took him on board it was largely to be a test-subject for many of their experiments that the Systems Alliance was not willing to undertake. Almost to their surprise, the man kept up his enthusiasm for Cerberus with every needle and incision, such was his ideological fervor to prevent the destruction of man by Turians once more.

In about a year of constant experimentation that Eric had survived, he had gone through and (to everybody's surprise) survived enough modifications to make him a huge walking investment. While much was the prototype for more refined processes they would apply to other agents, he had still endured enough surgeries to augment him into a capable field agent. While never being an assault specialist or the likes, he came to be a reliable infiltrator and "clean up man" who hid evidence of Cerberus involvement in events across the galaxy. Yet always he dutifully returned to the facilities where yet more surgeries would be performed on him, now in equal part experiment and simply facial reconstruction works to embrace a new identity. An almost constant in Cerberus since its very early days, Cimourdain would come to be a very trusted figure in the organization, speaking with the Illusive Man many times before at last being attached to a cell after seemingly having been on every corner of the Milky Way.

With connections everywhere, Cimourdain has to some degree come to be an intermediary between the Captain and Cerberus leadership, compiling different missions and assignments for the Comamnder to consider. While still keeping his job as a "clean up" man after the crew's missions, Eric is also somewhat of an "everyman" around the ship. He will fix minor broken systems like air conditioners or shower heating, cooking when there is no Mess-Sergeant, helping maintenance of personal equipment, or discretely purchasing things when on worlds.

To the Cell, some might consider Cimourdain a liability of sorts to themselves. Almost dangerously loyal, if ever the crew would consider en-masse defection he would likely thwart their efforts. Otherwise he remains somewhere between the "cool" and the "creepy" uncle. Always talking about strange, decades old interests or events. Asking questions too personal he insists would be normal back in his day, or offering to help people with personal matters they thought they had kept private.

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With the end of the Reaper war, Eric is somewhat changed. As time went on, many of the technologies that helped Cimourdain overcome his age were Reaper tech that was "fried" as the Reapers left Earth's orbit. While still outperforming his centennial years, things like senility can slowly creep in as he might suddenly forget where he is, or what he was doing. Moreover, he often struggles to differentiate between him or the many identities he has undertaken before telling random stories of his youth in an effort to "ground" himself in the world.

I will allow people to play non human characters, but there needs to be an extremely compelling backstory to explain why they got involved with a human-centric organization of freaks like Cerberus. Perhaps an unshackled AI housed in a bot frame along the lines of EDI, maybe a Salarian who joined years ago purely for the science unbound by the shackles of ethics. Maybe a Krogan who joined Cerberus back when it was just an alliance black-op seeing it as a powerful ally in venting hatred for salarians, turians, asari. It could even be that your character was "forced" to join when they began to be indoctrinated, but Cerberus used its technology developed on Horizon/Sanctuary to take control of this person. But in all of these cases, remember that you need to come up with a convincing reason for why they would stay with Cerberus after the reaper war ended.

Maybe the salarian sees Cerberus as still the best way forward for science, maybe the Krogan hasn't let go of grudges over the genophage even after its cured, maybe the character Cerberus used its reaper-control tech on is simply grateful for no longer being under the dominion of the reapers and has grown somewhat of a stockholm syndrome. Regardless it needs to be a convincing reason for why any alien would stick with Cerberus especially as with the existential threat of the reapers gone, "the ends justify the means" won't apply. At least, for a while....

Indeed, as the story progresses there may be more possibilities for aliens to join the team, but that will be later.

The Theseus Cell was formed in 2179 out of the merger of three cells. Cerberus defectors from the Dolon cell responsible for infiltration and intelligence gathering made contact with STG, knowing many figures they could approach were likely compromised. In turn, the Dolon cell lead STG to a Cerberus research facility, but not before loyalists tipped off Cerberus about the impending attack. STG’s attack was swift and brutal destroying most of the research staff, and indeed of the reinforcements sent to defend it from the Salarians as the Dolon cell’s loyalists slew their treacherous comrades. With the Dolon infiltration cell, the Galen research cell, and the Ulysses battalion all shells of their former selves which moreover had broken anonymity with one another, the Illusive man decided to reconstitute them into the new Theseus cell. Since then the Theseus cell has been united into a diverse but cohesive unit capable of performing a variety of tasks and without reliance on other cells that hyper-specialized ones often have.

Since its inception, the Theseus cell has absorbed many other weakened cells, individual operatives, and acquired recruits to perform its duties. At the conclusion of the Reaper war, the cell had about a hundred operatives.

-Eric Lasalle was a member of the Dolon cell, one of the foundational to Theseus. One of the loyalists that reported the betrayal of the rest of the cell in favor of STG to the Illusive Man, this has earned him respect from devoted ideologues and distrust from others.