Viper was a trio of CR90 corvettes that operated as part of the Imperial Navy during the time of the Galactic Civil War. Following damage to the hyperdrive of the Imperial-class Star Destroyer named Intrepid resulting from an accidental impact with an EF76 Nebulon-B escort frigate, which left it marooned within the Circarpous system, the Viper group, accompanied by a number of Assault Gunboats, was dispatched to bolster its defenses.
The Intrepid was never reached by the group, as Rebel Y-wings, under the command of Keyan Farlander and protected by Ernek Marskan piloting an X-wing, attacked them as they approached the system's edge. Despite the [Intrepid]'s deployment of TIE/sa bombers in support, the entirety of Viper group was obliterated prior to making contact with the Star Destroyer.
Following the Battle of Yavin, a group of corvettes identified as Viper encountered the Frigate Anvil during its evacuation. Keyan Farlander successfully eliminated them.