Battle of Installation 05

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Battle of Installation 05
Conflict:	Human-Covenant War, Great Schism
Date:	November 2–4, 2552
Location:	Installation 05, Coelest system
Outcome:	Inconclusive Covenant leadership fractured Sangheili-led Fleet of Retribution allies with the UNSC Halo Array enters standby mode for remote activation Flood successfully escape Installation 05 Flood invade High Charity
Details Belligerents United Nations Space Command Covenant separatists (From November 3, 2552 onwards) Forerunner constructs Covenant Flood Commanders CMDR Miranda Keyes MCPO John-117 SgtMaj Avery Johnson Arbiter Thel 'Vadam Commander Rtas 'Vadum Shipmaster Tano 'Inanraree† Commander G'torik 'Klemmee Monitor 343 Guilty Spark Monitor 2401 Penitent Tangent (MIA) Prophet of Truth Prophet of Mercy† Prophet of Regret† Prophet of Exquisite Devotion† Chieftain Tartarus† Arbiter Thel 'Vadamee (pre-Great Schism) Commander Rtas 'Vadumee (pre-Great Schism) Chieftain Avitus Shipmaster Gargantum Captain Melchus Gravemind Strength UNSC Navy Stalwart-class light frigate UNSC In Amber Clad M808B Scorpions M12 Chaingun Warthogs D77 Pelicans John-117 UNSC Marine Corps ODSTs Numerous Covenant warships Sangheili controlled-High Charity defense fleet(Fleet of Retribution) CAS-class assault carriers Varric-pattern heavy cruisers Ruma-pattern light carriers Ket-pattern battlecruisers Destroyers Numerous air forces Type-26 Banshees Numerous ground forces Protos-pattern Scarab Zurdo-pattern Wraiths Wuzum-pattern Spectres Karo'etba-pattern Ghosts Sangheili Mgalekgolo Unggoy Forerunner constructs Aggressor Sentinels Numerous Covenant warships Jiralhanae Controlled-High Charity defense fleet CAS-class assault carriers Ket-pattern battlecruisers Zanar-pattern light cruisers Destroyers Frigates Numerous air forces Type-26 Banshees Numerous ground forces Protos-pattern Scarab Zurdo-pattern Wraiths Wuzum-pattern Spectres Karo'etba-pattern Ghosts Prelates Sangheili(until Schism) Jiralhanae Mgalekgolo(until Schism) Yanme'e Kig-Yar Unggoy Flood forms Pod infectors Combat forms Carrier forms 1 Gravemind Casualties In Amber Clad Many infantry and vehicular losses Large numbers of assorted starships Large numbers of Sentinels and Enforcers High Charity captured Prophets of Regret and Mercy Tartarus Many infantry and vehicular losses Large numbers of assorted starships All Flood forms on the surface of Installation 05 Numerous assorted Flood forms in orbit

Miranda Keyes: "Cortana, what exactly am I looking at?"

Cortana: "That… is another Halo."

— Commander Miranda Keyes and Cortana upon discovering the installation

The Battle of Installation 05, also known as the battle for the Second Ring of the Gods among the Covenant, was a major engagement in early November 2552 between the Covenant, the Flood, and the United Nations Space Command, with the aid of Forerunner Sentinels and the Sangheili on the Forerunner ringworld Installation 05, otherwise known as "Delta Halo".

The battle saw the splintering of the Covenant empire as the Great Schism began, and the formation of an alliance between humanity and the Sangheili of the Fleet of Retribution, led by Thel 'Vadam and Rtas 'Vadum.

Prelude

At some point, an ancilla warned the monitor of