Ambush at the Quarry
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After the retrieval of the Durance known as "the Didact's Gift," the crew of the UNSC Infinity learned that some of the Promethean Knights they were fighting had been humans digitized by the Composer during the New Phoenix Incident. After learning that the mysterious artifact brought onboard the Infinity had somehow been in New Phoenix at the time, Spartan Gabriel Thorne inadvertently activated it and was translocated to "the Cauldron" where he was ultimately captured and dragged to "Librarian's Rest."
After Fireteam Crimson succeeded in defending Magma Base in "the Cauldron" from Covenant forces, Roland detected Thorne's IFF transponder nearby. However, while Crimson found the transponder, Thorne was already gone though there was signs of battle. Roland was able to determine which way Thorne had been taken and Spartan Jared Miller ordered Crimson to follow Roland's directions and chase after Thorne.
Hunt for Gabriel Thorne
Roland tracked Thorne to the "Quarry," but he had been carried out of surveillance range by the Sangheili and he could only give a general direction. As Spartan Commander Sarah Palmer remained out of contact, Spartan Jared Miller, filling in for her, ordered Roland to try to contact Palmer as she needed to know what was going on and instructed Fireteam Crimson to try to find and rescue Thorne.
As Crimson proceeded, Roland detected two likely spots that Thorne could've been taken, the first being a nearby butte. As Crimson investigated, they were attacked by Covenant forces, including Kig-Yar Snipers, turrets, Ghosts and Wraiths. Crimson discovered that Thorne was not at the first location and cleared out the remaining Covenant in the area, including reinforcements dropped by Phantoms.
Roland detected a higher than normal number of Covenant at the other end of the "Quarry," suggesting that there was something worth guarding in that location such as a captured Spartan. Crimson fought their way to the end of the "Quarry" which was heavily guarded by Covenant forces including Wraiths and Ghosts. Despite the heavy resistance, Crimson managed to clear the area, but only found a collection of stolen UNSC gear, vehicles and weapons. However, there was no sign of Thorne and Roland had lost the trail. With the search-and-rescue mission a failure, Miller called upon Spartan Robert Dalton to send in a Pelican to extract Crimson, but was warned that it would take some time.
The Covenant started sending in massive waves of troops via heavy orbital insertion pods and Phantoms to attack Crimson. With the help of the stolen UNSC gear, Crimson managed to repel each successive wave despite being heavily outnumbered. However, several Hunters and Wraiths were deployed in the area and at Miller's request, Dalton dropped ordnance pods containing Spartan Lasers. With the heavy weapons, Crimson managed to eliminate the Hunters and Wraiths, seemingly ending the Covenant attack.
Fireteam Crimson captured
With the Covenant gone, Dalton reported that he finally had the Pelican Miller had requested to extract Fireteam Crimson. Miller directed both Crimson and the Pelican to the top of the nearby butte for the extraction and Crimson made their way back to the top of the butte.
As Crimson awaited the approaching Pelican 653, an orbital insertion pod suddenly crashed through the dropship, destroying it and killing pilot Ryan Frank. Roland warned of numerous approaching enemy forces as multiple Banshees, at least five Phantoms and a CRS-class light cruiser surrounded Fireteam Crimson in a surprise ambush. Rather than kill Crimson, the Covenant captured them and transported the Spartans to "Lockup."
Miller and Dalton eventually managed to locate Fireteam Crimson at "Lockup" and launched a diversionary bombardment that freed the Spartans of their restraints. Fireteam Crimson subsequently rescued Icebreaker squad and together they stole a Phantom to escape from Covenant custody.
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