The Massive Attack was Darth Odysseas' Victory-class II cruiser that was in use during the Rebellion Era. It was the only ship that Darth Odysseas used to travel and fight against the rebels.
It participated in numerous battles as it was the only ship that Darth Odysseas was using.
In a battle above the planet Geonosis that the Massive Attack participated, it was almost destroyed due to mistakes from the ship commander.
You have failed me for the last time, commander.
—Darth Odysseas before he killed him with the Force.
After that, he ordered the other ship commander to get the ship in a safe place. However, before that, Darth Odysseas landed on the surface and met a small team of clone troopers and AT-ST's in order to lead them in battle. After this battle on Geonosis, the ship was fully repaired but the maximum capacity was reduced by 5% after the orders from Darth Odysseas.
One of the most notable deeds of Massive Attack was the defense of the planet Coruscant, which was Darth Odysseas' homeworld. When he saw that the planet needed reinforcements, he instantly took Massive attack and many TIE fighters and flew over the planet and met the other Empire ships. It managed to destroy a great number of X-Wings, Y-Wings, and Corellian corvettes, and it successfully defended the planet Coruscant. If Massive Attack was not there, the Rebels would probably manage to destroy the Empire defense line and land on the Coruscant's surface, destroying the weak defenses that this planet had at this period of time.
When the Second Death Star was destroyed in the Battle of Endor, Massive Attack was very close to Death Star. It was unknown if it was destroyed or if Darth Odysseas managed to escape into hyperspace. The fate of the ship and its owner remained unknown after the fall of the Galactic Empire.