Operation: Up-Stream

As part of the South American Campaign, taking place during the Battle of Earth in 2552, Operation: Up-Stream was a counter offensive engagement between the UNSC forces protecting Earth and the Covenant invasion forces, primarily those of the Fleet of Furious Redemption. With invasion parties commencing across Earth the UNSC Sirens Bane was sent planet-side to prevent excavation attempts underway in the thick of the Amazon Rainforest. With substantial enemy air in the air the Sirens Bane was forced to deploy ground forces rather than engage the covenant threat directly. Four pelicans were deployed along with a squad of ODST's to infiltrate and sabotage the operations while the Sirens Bane occupied local enemy air units.

Into the Thick
Of the four pelicans deployed all successfully made it to their landing sites, the use of vehicles during the operation was impossible due to the thick forestry forcing the pelican pilots to wager the security of a far away landing zone with the missions effectiveness of risking a closer drop-off point. Ultimately settling in a cratered waterfall basin the marine forces were deployed and began the long trek through the dense jungle.

ODST's team Ethereal was deployed via the Sirens Bane and inserted into the excavation site under the cover of a small carpet bombing run by the Bane. Once active on the ground Ethereal fought through the minimal ground forces who were setting up the excavation site and attempted to halt the operations enough to garner some attention in order for the Sirens Bane to deliver debilitating blows to the CCS-class Battlecruisers overhead. While dealing strictly in harassment until the marine reinforcements were able to arrive Ethereal allowed the Sirens Bane to disable one of the Covenant Battlecruisers. With the arrival of the marine reinforcements charges were placed on all the covenant ground structures. Meanwhile a second battlecruiser broke off and targeted the Sirens Bane which was forced to flee, leading the battlecruiser off. The third and final CCS fired its excavation beam in a single pulse disturbing the apparently fragile ground and revealing a subterranean pit to which Ethereal and the surviving marines fell into. Covenant forces quickly followed. Forced deep into the cavernous underground Ethereal would become cornered. Accidentally activating, after an unknown period of dormancy, the Retriever sentinel targeted the covenant forces initially, wiping them all out before seemingly scanning Ethereal Squad for bio-permissions to be at the site. Apparently failing the Sentinel then targeted Ethereal who used what remained of their demolitions to trap and destroy the sentinel.

After destroying the pursuant battlecruiser the Sirens Bane returned and fired upon the final covenant cruiser. Cruiser began excavating more of the site with its energy projector flooding the sink hole with molten rock. A Pelican from the Bane was sent into the collapsing cavern and successfully evacuated the survivors while the Bane fired upon the battlecruiser successfully destroying it, albeit taking considerable damage.

Upon on-boarding the UNSC Sirens Bane was immediately ordered to assist in the defense of the Macapa Space Tether nearby in Northern Brazil.

Trivia

 * Inside the bowels of the subterranean Amazon the forces discovered forerunner and non-forerunner ruins, seemingly melded together and built off of one another. While only helmet cam footage remains, scientists are still hoping to find clues as to the origin of the site and its protector.