On the night of July 23, 2552, the Fleet of Valiant Prudence, including Ardent Prayer, was deployed as an advance force to the human planet Reach. Over the following weeks, the fleet engaged human targets across the planet. After the fleet's flagship, the CSO-class supercarrier Long Night of Solace, revealed its location during the Fall of Reach, SPARTAN Catherine-B320 formulated Operation: UPPER CUT, a plan to destroy Long Night of Solace through the use of an improvised "slipspace bomb."
On August 14, SPARTAN-B312, Jorge-052, and several YSS-1000 Sabre pilots, with the assistance of the UNSC Savannah, boarded Ardent Prayer; the UNSC intended to use the Ardent Prayer to deliver the improvised bomb to the Long Night of Solace, while the former was en route to refuel with the supercarrier. As the boarders made their way through the corvette, they assaulted the bridge. The bridge crew were caught unaware; although 'Moretumee and his companions defended themselves, they were killed by the boarders. Ardent Prayer then continued toward Long Night of Solace and the bomb was activated, destroying both vessels.
- Halo: Reach (First appearance)