The Executor-class Star Dreadnaught (commonly known as a Super Star Destroyer) were large command ships that appeared in the Star Wars franchise. The first of three Super-Class Star Destroyers in service before the Battle of Hoth, the Executor was Darth Vader's flagship while he hunted down the main Rebel Alliance base. At 8,000 meters long, it was the largest traditional starship constructed by the Imperial Navy.
Super Star Destroyers were Imperial Navy command ships and were assigned only to the most important and prestigious missions. Being assigned to these vessels were regarded by Navy officers as a the fast track to promotions
In a military sense, the Super Star Destroyer was somewhat impractical, since a small ship could fulfill its mission duties. Rather, the Super Star Destroyer represented the Emperor's unlimited power and resources. The Imperial Star Destroyer frightened worlds into submission; the Super Star Destroyer terrorized them beyond the capability for resistance. At over five times the length of a standard Star Destroyer, it could conquer without firing a shot, and so win the battle before engaging the enemy.
Bristling with over a thousand weapons, including turbolasers, concussion-missile tubes, tractor-beam projectors and ion cannons, the Super Star Destroyers wielded awesome firepower. They held two full wings of TIE Fighters, for a hundred and forty four ships, as well as two hundred other combat and support ships. For ground assaults, Super Star Destroyers maintained a full corps of Stormtroopers, 38,000 ground troopers, three prefabricated Imperial garrison bases, and enough walkers to decimate any Rebel base.
The Executor was built at the starship yards of Fondor after being designed by Lira Wessex, designer of the Imperial Star Destroyer. Upon its completion, the ship was presented to Lord Vader as a headquarters ship for his quest to find the Rebel Alliance's command base. It was originally commanded by Admiral Kendel Ozzel, but after his unfortunate death at Vader's hands for incompetence, Executor Captain Firmus Piett was promoted to Admiral and given command of the vessel by Lord Vader.
The Executor was destroyed at the Battle of Endor. After its shield generators were destroyed, Rebel fighter pilot Arvel Crynyd smashed his A-Wing fighter into the bridge of the Executor, killing Piett and the bridge crew. With the ship crippled and damage-control crews unable to seize command using the auxiliary control centers, the Death Star's gravity pulled the Executor into the immense battle station. The Executor exploded on impact with the Death Star, also causing significant damage to the incomplete battle station, and forcing many of the Death Star's crew to evacuate before the battle station was destroyed as well. Many of the Empire's best young officers were killed in that incident, making the Rebellion's eventual victory over the Empire far easier, as with the loss of the Emperor, Darth Vader, the Executor, and the Death Star, the Empire was unable to recover from such huge losses of personnel and equipment.
Only three Super Star Destroyers were built and put into service by the Battle of Hoth, and of the three, only the Ravager survived after the Battle of Endor. When the Ravager was destroyed at the Battle of Jakku, Super Star Destroyers were no more.
In the Legends continuity, the Executor-class was more common, though the amount of ships built was intentionally left ambiguous by the Empire. After Palpatine's death at the Battle of Endor, Super Star Destroyers became the flagships of the many Imperial warlords. One ship, the Lusankya (which was built at the same time as the Executor), came under the command of Ysanne Isard, the first leader of the Imperial Remnant. After Isard's death during the Bacta Wars, the ship came under command of Wedge Antilles, and served in the New Republic Defense Fleet until its destruction during the Yuuzhan Vong War. Another Super Star Destroyer, the Reaper, was under the command of Pentastar Alignment leader, Ardus Kaine. A later Imperial Remnant leader, Natasi Daala, commanded the Knight Hammer. Other ships of the class included the Annihilator (destroyed by the Zann Consortium at Kuat shortly after the Battle of Endor), Iron Fist (commanded by Imperial warlord Zsinj), Aggressor (commanded by Grand Admiral Grung), and Enforcer.