Upsilon Team was a SPARTAN-III unit that participated in numerous campaigns over the course of the Human-Covenant War. Formed from a group of survivors in the aftermath of Operation: PROMETHEUS, they took to the frontlines to inflict maximum damage towards their Covenant foe and would play pivotal roles in several campaigns, including the Siege of Fargad. Operating frequently alongside the Spartan Tau Team, they relied on superior firepower and heavy weapons to get the job done while their counterparts took subtler ways to eliminate the enemy.
In August of 2552, Upsilon were awaiting redeployment on Reach when news arrived of a Covenant invasion. To counter this, they were immediately diverted to assist with the planet's defence and over the course of several weeks would participate in several battles, including Operation: DROP KICK and the Siege of New Alexandria. However, the team would see heavy losses during this period as Reach slowly but surely fell to the Covenant. By August 30th, all but one member of Tau had died on Reach as its sole survivor escaped alongside a group of Spartans and ODST's aboard a UNSC Frigate. The remnants of both SPARTAN-III teams were incorporated into Sigma Team shortly afterwards, and Upsilon was officially dissolved in 2553.
This list is accurate as of March 2553 and Upsilon Team's disbandment.
The team was originally made as a group of SPARTAN-III redshirts for the purpose of dying on Reach shortly after the author joined the site, though their backstory has been expanded on in other stories since then.