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Mission aboard Mona Lisa
Orlav was part of the Marine detachment sent to conduct reconnaissance on the prison ship Mona Lisa drifting in the debris field of Installation 04. Unknowingly, the Marines were actually operating under orders of the Office of Naval Intelligence, which had used the Mona Lisa as a laboratory for experimentation on the parasitic Flood.
The Marines would board the ship through a cargo bay and soon encounter a group of unarmored and unarmed Sangheili, dispatching them with ease. Shortly after this, the Marines received new orders to initiate the Cole Protocol by purging the Mona Lisa's NAV databases. Orlav was assigned to Corpsman Benti's party, also consisting of Clarence, Gersten and Tsardikos. They were to make their way to the ship's engine room and destroy the backup navigation database held there. Lopez assessed that Orlav was proficient at reconnaissance but could not improvise, and as such, she had Benti lead the team instead of Orlav. Along the way, Orlav would provide intelligence for the team, using a tablet computer to analyze the schematics of the ship and find the fastest way to their objective. They would cut through a series of access tunnels, only to run into a locked door. Orlav then found another route, which forced them to pass through the ship's recycling plant. There, their party was attacked by a horde of Flood, which chased them through the bilges. During the skirmish, a Flood form slashed Orlav in the back, infecting her. Quickly turning into a combat form, she attacked Gersten, biting him in the cheek and transmitting the infection to him, before being promptly shot by Clarence.
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