Ballistas were motherships of great capacity, able to host smaller ships in its bay, as well as carry a large amount of military. Ballistas should be commanded by a Tercero or higher.
Ballistas could carry the following additional armaments
- 1500 crewmen
- 20 troop transports
- 15 large shuttles for cargo and equipment
- 20 small passenger shuttles,
- 50 long-range patrol craft
- 200 kindjals.
Around 88 BG, Ballistas were updated with a new kind of model.
About 83 years after the Battle of Corrin, Manford Torondo blackmails Emperor Salvador Corrino into giving Manford's Butlerians a fleet of 200 mothballed Ballistae. This fleet attacks the recently rediscovered machine shipyards and the defending Venhold forces. While the orbital shipyards are destroyed with over 6000 Venhold employees aboard, the Butlerian fleet also sustains heavy casualties thanks to daring tactics employed by the defenders and also due to the fact that they are using outdated ships. Nearly 100 Ballistae were destroyed with thousands aboard. The rest are taken to Salusa Secundus to intimidate the Landsraad.
Following the destruction of the shipyards, Josef Venport began to arm Venhold ships to protect them against Butlerian aggression. Using top-of-the-line weapons and shields, Venhold ships proved to be far superior to the outdated Ballistae still in use by the Butlerians, and a number of Butlerian ships were destroyed in small engagements over contested worlds, with the Butlerians frequently opening fire first.
As the conflict escalates, Manford Torondo brings his fleet of Ballistae to Salusa Secundus, unaware that Josef Venport's fleet is laying siege to the Imperial capital world in an attempt to force Emperor Roderick Corrino into siding with him against the fanatics. With the arrival of the Butlerian fleet, Venhold ships are forced to fight a two-pronged battle against the old but numerous Ballistae and the smaller force of Imperial warships defending the planet. Even so, Venhold would have likely won anyway, if Norma Cenva hadn't ordered all ships to jump to Arrakis immediately in order to protect the secret Venhold spice stockpile that was being raided by Freemen under Roderick's orders. Assuming Venport retreated because of them, Torondo keeps the Ballistae in orbit of Salusa, ostensibly to protect the planet, but also as a form of intimidation.
After Manford Torondo receives a cache of forbidden atomics from a devout Landsraad nobleman, left over from the Jihad, he orders a strike at the heavily-defended Venport Holdings headquarters on Kolhar, distributing the atomics throughout his Ballistae. Unprepared for the use of atomics, the planet's considerable defenses fall in a matter of minutes, and the Butlerians scour it with nuclear fire.
In response, Venport orders a retaliatory strike at Lampadas, the home planet of the Butlerian leader, bringing most of his fleet that engages the Ballistae in orbit. Despite the numerical and technological superiority of Venhold ships, the Butlerians manage to inflict heavy losses on them due to their use of suicidal tactics, such as ramming and firing lasguns at shields. With both fleets engaged and seriously damaged, Admiral Umberto Harte, whose force of conventional FTL ships has been sent by Emperor Roderick to ambush Butlerian ships at Lampadas, chooses this moment to perform a sudden strike at both weakened enemies. His battlegroup deals a devastating blow to both Butlerians and Venhold, forcing the latter to jump away. The surviving Ballistae are then confiscated by Imperial forces to be refitted for use in the Imperial fleet.