Marciniak was a member of Marius Blackwood's platoon. He was a close friend of Marius, and was the second to die in combat.
Marciniak served alongside Marius Blackwood, Cione, Stoltzfus, Billy Tallman all through their days in the academy. They had been part of the same platoon, and had saved one another on more then one occasion. After their platoon broke up, they all agreed to meet every year in Shiloh in a bar called the Shed.
Marciniak vanished near Char. He was the second one to die of the former platoon.