Raid on the Warrens
From Halopedia, the Halo wiki
While searching for the missing Spartan Gabriel Thorne, Fireteam Crimson was ambushed at the "Quarry" and captured. Taken to "Lockup," Crimson managed to escape with the help of Jared Miller and Robert Dalton and rescued Icebreaker squad who were held captive at the facility as well. Lieutenant TJ Murphy of Icebreaker squad successfully managed to hijack a Covenant Phantom which he and Crimson used to escape from "Lockup."
Following their escape, Crimson's Phantom, mistaken by the Covenant for one of their own, was ordered to land at "Control." Crimson was able to infiltrate the facility and access three Covenant comm relays, allowing Roland to implant computer worms into them in order to access the data. Crimson then made their escape after eliminating the Covenant reinforcements.
Accessing the facility
From the data recovered at "Control," it was determined that there was a Covenant central intel center located in the "Warrens" and Commander Sarah Palmer ordered Fireteam Crimson to check it out. Lieutenant TJ Murphy dropped Crimson off near the facility entrance in their stolen Phantom where they engaged the guarding forces, including a Sangheili Zealot. Crimson managed to eliminate the guarding Covenant, but the door wouldn't open. In response to Crimson's incursion, a Phantom dropped off more Covenant reinforcements which were quickly eliminated by Crimson.[note 1]
With the Covenant forces eliminated, Spartan Jared Miller located an alternate route blocked by a Covenant energy shield. Miller directed Crimson to a control console which they were able to use to drop the shield and move inside a passage leading into the structure. Inside, Crimson was attacked by Stealth Sangheili which they were able to eliminate without suffering casualties.
Accessing the intel center
Entering the massive cavern containing the Forerunner structure, Crimson eliminated the Covenant guards. As Crimson moved in close to the Forerunner structure, their presence attracted the presence of Promethean Knights and Promethean Watchers which attacked Crimson. Despite heavy resistance, Crimson managed to eliminate the Promethean forces and Miller detected a control console rigged to a light bridge system. Crimson activated the light bridges, but in the process, drew more Promethean forces to their location. With the help of Covenant Banshees parked in the cavern, Crimson was able to eliminate the Prometheans and clear the area.
With the enemy forces gone, Palmer ordered Crimson to activate the intel center which was located at the far end of the light bridges. Crimson accessed the Covenant computer, allowing Miller to extract the information and begin running it through translation software. As Crimson began to leave, a Covenant Phantom entered the cavern and dropped off reinforcements as more Prometheans translocated in. As Crimson fought their way out, Miller learned that the Covenant were engaged in an archeological dig. With Fireteam Switchback available to investigate, Palmer ordered Miller to contact Switchback's handler and dispatch them to investigate. Shortly thereafter, Miller discovered the location of a Covenant supply depot near Crimson's position and Palmer decided to redeploy Crimson to investigate.
Emerging outside, Crimson found the area once again occupied by Covenant forces with Phantoms dropping off reinforcements including a deployable lookout tower and a Hunter pair. However, Crimson managed to eliminate all of the Covenant forces and were extracted by Murphy's Phantom.
Based on the information recovered from the intel center in the "Warrens," Crimson was redeployed to take out the Covenant supply depot while Fireteam Switchback handled the Covenant archeological dig. Though Crimson succeeded in their mission, Switchback came under heavy Covenant attack and contact was lost with them. Crimson subsequently finished Switchback's mission, though they had vanished without a trace by the time Crimson arrived.
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