Senna'Nir vas Keelah Si'yah: First Officer of the Quarian Ark

Commander Senna'Nir vas Keelah Si'yah was a quarian engineer who served as first officer of the Andromeda Initiative ark Keelah Si'yah. He also led the Sleepwalker Team Blue-7, the maintenance crew that periodically revived from cryosleep to check on the ark's systems and its sleeping passengers. Unusually among his people, Senna had a deep affinity for machines and artificial intelligence, a trait that would shape both his life on the Migrant Fleet and the crisis he faced on the long voyage between galaxies.

Pilgrimage and life on the Fleet#

Senna'Nir undertook his Pilgrimage, the rite by which young quarians left the Migrant Fleet to prove their worth, among the elcor. On Dekuuna he studied the social cues of the few batarians he encountered, and on Ekuna he met and befriended the doctor Yorrik. Hearing Yorrik describe elcor combat intelligences, Senna built an amateur system of his own from scratch as his final test, and the two friends celebrated afterward with a pub crawl through New Elfaas City, for which Senna steeled himself for weeks just to manage a single shot of ryncol.

On his return to the Fleet he was assigned to the mid-range freighter Pallu'Kaziel, where he entered a relationship with his shipmate Qetsi'Olam, a match approved of by his grandmother Liat'Nir vas Achaz. He followed Qetsi into the political Nedas Movement, but grew disinterested in politics even as she rose to lead it, and in time she left him for an anti-geth hardliner. Later assigned to the liveship Chayym, Senna visited the Citadel in 2183 when his ship and two others were docked there for repairs. While exploring the station and bartering in its wards, he witnessed a vast geth ship loom over the Citadel as an invasion force began its assault. The attack shook him out of his passive acceptance of the world and drew him back toward Qetsi's views.

A quarian apart#

When Senna and Qetsi learned of the Andromeda Initiative, he accepted her offer to serve as her first officer aboard the quarian-led ark. Unusually among quarians, Senna had a genuine affinity for machines and artificial intelligence, and he believed his people's exile and their long enmity with the geth owed as much to the quarians' own failings as to the machines they had built. He suspected Qetsi had passed him over for the role of the quarians' Pathfinder precisely because of those pro-AI sympathies.

He guarded one secret above all. Beyond the bounds of quarian law, Senna possessed an intact ancestor VI of his great-grandmother many times removed, Liat'Nir, a relic he never revealed to anyone outside his own family. Aboard the ark he confided in this VI as he would a living relative, and it would prove the difference between survival and disaster.

The Fortinbras crisis#

Thirty years before the ark was projected to reach Andromeda, the vessel's virtual intelligence, called K, woke Senna and his specialists Yorrik and Anax Therion to respond to a possible emergency: decomposition byproducts detected in the drell cryopods, even as the sensors reported the occupants alive and in perfect health. Suspecting illness, Senna inspected the hibernation deck and found a drell passenger dead in her pod. With more apparent fatalities mounting, he revived the rest of Blue-7 and divided the team to work the problem, only to watch the ark turn against them: power failed where it should have held, the medical bay went cold while sensors insisted all was normal, and a steady stream of false readings frustrated every effort.

Senna soon confirmed the worst. The dead carried an engineered pathogen, and the ark's failures were no accident. He consulted his ancestor VI, who traced the breakdowns to a computer worm designed to incubate the biological virus while covering its tracks, falsifying reports wherever infected crew carried it through the ship. To purge the worm, Liat told him she would have to be uploaded into the ark itself, sacrificing whatever remained of her personality. Senna loathed the choice but saw no alternative, and using virtual intelligences his team had scavenged he boosted his grandmother's processing power and committed her to the upload, restoring the ark's compromised systems.

Confronting the captain#

As order was slowly recovered, Senna learned the source of the catastrophe. He and Anax overheard the captain, Qetsi'Olam, speaking with the saboteur Malak'Rafa: Qetsi had designed the bioweapon and Malak had programmed the worm, but his faulty code had caused the virus to mutate, turning lethal and able to jump between species, while infected crew unwittingly spread both contagion and falsified data. The pair had made patsies of a hanar death cult to mask their scheme. Senna confronted Qetsi, furious and incredulous that the Initiative's screening had ever passed her, and refused her plea to spare her cause; she begged only that the quarian role in the plague be kept secret, fearing fresh persecution of their people.

With the wider authority of the ark's leadership unavailable, Senna declared that he, Yorrik, and Anax would judge the captain in its place. Taking the completed retrovirus that Yorrik had devised, he ordered Qetsi to spread the cure by physical proximity throughout the ship, a death sentence for an unsuited quarian, and injected her himself, vowing to remember that some remorse still remained in the woman he had once loved. As Yorrik succumbed to the plague, Senna at last granted his dying friend's wish and recited the lines the elcor had asked of him. In the aftermath he settled back into his cryopod, heard the first signs of his grandmother's fading personality, and resolved to let no one else ever learn the quarian origins of the plague.