Quadrant 4 was a region in the northern hemisphere of Harvest where a UNSC aerial reconnaissance Hornet, on orders from Professor Anders, discovered a battalion-sized mass of Covenant. Sergeant John Forge was sent on a reconnaissance patrol to determine the strength and intention of this mass, but the Covenant presence had already moved north into a Forerunner relic. It is likely that this patrol saved Forge from being present at the Covenant's destruction of Alpha Base.[1]

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