Battle of the Quarantine Zone
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Overview
One of the few battles of the 9th Age of Reclamation in which all four of the main factions took part. The Covenant and UNSC fought through the Quarantine Zone in search of the Index, known to the Covenant as the Sacred Icon. Both parties had to battle their way through legions of Flood and the Forerunner machines designed to halt the parasite outbreak.
The Battle
It was one of the largest pitched battles that occurred on the surface of Delta Halo. Boiling plasma, solid slug rounds and plasma sword met decomposing, mutated flesh on the snow covered, ash-laiden wasteland that is the Quarantine Zone. All four races reportedly fought one another in this confined space, the Covenant and Human dead only providing more troops for the Flood menace. Sentinels and Enforcers had kept the parasite at bay for untold centuries within the Sentinel Wall, even with their leader 2401 Penitent Tangent held captive by the Gravemind. The deactivation of the containment field forced them to spread their numbers over a much larger area which ultimately proved too much, seeing as the Flood eventually took over the human ship, UNSC In Amber Clad, left near the library by human forces.
The Arbiter of the Covenant was sent to the surface of Installation 05 to retrieve the Sacred Icon. Dropped directly into the Sentinel Wall by a Phantom transport, the Arbiter fought mostly alone, only aided by a small number of the original landing party (several Grunts and Jackals), through numerous Forerunner constructs to reach the control centre for the containment shields. By lowering these shields, the Covenant soldiers learned many Human Marines had made it through the wall only to be swiftly infected by the Flood. More Covenant warriors soon entered the Quarantine Zone, unfortunately exacerbating the Flood outbreak.
This breach of containment led to the rapid growth in the Flood's numbers as they assimilated both humans, from the UNSC In Amber Clad, and Covenant warriors. With these new hosts, the Flood gained access to more sophisticated equipment, weapons and combat vehicles, magnifying the danger the outbreak presented immeasurably. The Flood showed a bit of a tactical genius by destroying one of the Forerunner Sentinel Constructor ships. It ceased to float above the Quarantine Zone and produce countless Sentinels and Enforcers.
Despite this new and surprising defense, Covenant and Human forces were able to battle their way through the legions of Flood and Sentinel constructs. Elements of both parties eventually reached the Gondola entrance points to the Library of Delta Halo. Commander Miranda Keyes, Sgt. Johnson and a number of Marines entered the Library first. They were quickly followed by the Arbiter and a squad of Elite troops. Rtas 'Vadumee stayed behind to defend the Gondola station, presumably he did not do so alone.
The Library
Human forces had gained access to the Library first, but only by a matter of minutes. Upon arrival within the Library it was clear that the humans had faced stiff opposition, all but four of their number had died combating the Flood and Sentinels already within its walls.
The Arbiter found Miranda Keyes and Sergeant Johnson within the Index Chamber having retrieved the Index seconds before his arrival. Sergeant Johnson was ready, armed with a Battle Rifle, along with Miranda Keyes who was reaching for the Index holding on to one of the Gravemind's tentacles. Miranda secured the Index and drew two SMGs. Johnson called for his marines, but received no answer and armed his weapon. The Arbiter proved his worth as a warrior once again, incapacitating both Johnson and Keyes in a matter of moments. The arrival of Tartarus within the Chamber signified the beginning of the Civil War of the Covenant as he attacked the Arbiter, sending him plummeting to his doom deep within the Library, towards the Gravemind.
There is a downed pelican near the gondola entrance. It is believed that Miranda Keyes,Sergeant Johnson and the other marines came in that pelican after the shield went down.