The first UNSC encounter with the CRS-class light cruiser was during the Battle of Chi Ceti in 2525. The ship inflicted heavy damage on the UNSC Commonwealth before being destroyed by a team of SPARTAN-IIs. Several of these vessels were deployed and used over Reach during the Covenant's invasion of the planet.[4] After the conclusion of the Human-Covenant war, the CRS-class formed the backbone of the Covenant Remnant Fleet which deployed huge numbers of them to Requiem during the years before the First Battle of Requiem.