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A few months after the Dominion's founding, Alpha Squadron was dispatched to Char in order to "flush out" the zerg. Alpha Squadron was on the receiving end of the casualties however, a receiving end which included the zerg overrunning the science vessel Amerigo. In response, a demolition team, Jacobs included, was sent to investigate and, if any zerg were present, destroy it.
The marines had brought a high yield explosive with them, along with a number of beverages. While enjoying such a substance along with his teammates, Jacobs was suddenly impaled by a hydralisk's claw from behind, piercing his skull. Seconds later, his corpse was lifted up and away from his fellow teammates.
It appears that Jacobs possessed an O blood type.