Sergei Milanich is one of the Cyberneticized Humans that was not a former SPARTAN II, and is thus much younger that most of the others. Born in Moscow, Russia in 2552, Sergei joined the UNSC military at eighteen and, eight years later, in 2578, he was shot in the back with a Beam Rifle by a Jackal Sniper in a UNSC assault on an outpost of the Kig-Yar Pirates. Milanich was paralyzed from the waist down and confined to a wheelchair, but still, he swore he would find a way to kill the Jackal that crippled him no matter what it took. Sergei's chance came in 2587, when, with the help of the Machina, the UNSC started the Human Cybernetization Project. Sergei immediately volunteered.