Viper was a group of three CR90 corvettes that served in the Imperial Navy during the Galactic Civil War. After the Imperial-class Star Destroyer Intrepid's hyperdrive was damaged in an accidental collision with an EF76 Nebulon-B escort frigate, leaving it stranded in the Circarpous system, Viper group was sent, along with several Assault Gunboats to reinforce it.
However, before the group could reach the Intrepid, they were attacked at the edge of the system by a group of Rebel Y-wings, led by Keyan Farlander, escorted by Ernek Marskan in an X-wing. Although the Intrepid sent TIE/sa bombers to help, all of Viper group was destroyed before they could reach the Star Destroyer.
After the Battle of Yavin a group of corvettes named Viper came across the Frigate Anvil being evacuated. Keyan Farlander managed to destroy them.
- Star Wars: X-Wing Tour of Duty: Imperial Pursuit (First appearance)