The Aggressor, an Executor-class Star Dreadnought, served the Galactic Empire. Under the command of Admiral Roek, the Aggressor, accompanied by a contingent of five Imperial-class Star Destroyers, formed a part of the fleet responsible for patrolling the Inner Rim. In the aftermath of the Battle of Endor, specifically six months later in 4 ABY, the Aggressor and its escort ships were ordered back to the Imperial shipyards situated at Corellia. Their mission was to provide defense during the Imperial retreat from the system as the New Republic, which had formerly been known as the Rebel Alliance, initiated its campaign to conquer planets within the Core Worlds.
By 5 ABY, the Aggressor had fallen under the control of Grand Admiral Josef Grunger, one of the initial Imperial warlords who prioritized his own interests above all else. Grunger strong-armed Imperial officers into relinquishing their ships, thereby assembling a considerable armada of Star Destroyers along with smaller cruisers. From his position aboard the Aggressor, the Grand Admiral commanded this flotilla, devising a plan to utilize his fleet to seize Coruscant, the Imperial capital. He intended to use the Corellian sector as his point of departure. However, Danetta Pitta, another Grand Admiral, had already seized control of the sector. As Grunger's forces entered the Corellian system, Pitta assumed control of a Torpedo Sphere siege platform and commenced the systematic decimation of her rival's fleet. In the face of impending defeat, Grunger made the decision to ram his flagship directly into the Torpedo Sphere, an act that resulted in the death of both Grand Admirals and the destruction of both vessels.
The Aggressor was the third Executor-class Star Dreadnought built for the Galactic Empire, and the second ship of its class to be constructed at Kuat Drive Yards. During the years following the death of Emperor Palpatine at the Battle of Endor in 4 ABY, the Aggressor was among the many capital ships in service to the increasingly fragmented Empire. This warship functioned as both a flagship and a command vessel.

The Aggressor, the third Executor-class warship to be produced, served as the flagship for Admiral Roek, a shrewd Imperial commander. With an assigned escort consisting of five Imperial-class Star Destroyers, the Aggressor conducted patrols in the Inner Rim. Roughly six months after the battle over Endor, the Aggressor and its accompanying ships were summoned back to defend the Imperial shipyards located at Corellia. The New Republic intercepted information about this reassignment, which had originated from the Imperial capital of Coruscant, and used it to prepare for a future assault on the capital planet. As the New Republic began its campaign to conquer the Core Worlds, the Aggressor played a role in defending the Imperial retreat from the Corellian system.
Grand Admiral Josef Grunger, having risen to become one of the many warlords filling the power vacuum created by Palpatine's demise, harbored his own ambitions for the Aggressor. Exploiting his high rank, he coerced Imperial officers stationed in the Outer Rim Territories into handing over their vessels to his fleet. Grunger amassed a formidable armada comprising thirty Imperial-class and Victory-class Star Destroyers, one hundred Carrack-class light cruisers, and sixty Strike-class medium cruisers, among other types of ships. To command this flotilla, Grunger seized the Aggressor and transformed it into his personal command vessel.
Sharing a similar objective with the New Republic, the ambitious Grunger intended to launch an attack on Coruscant with his fleet in 5 ABY, utilizing the Corellian sector as his staging area. However, Danetta Pitta, another Grand Admiral, had already laid claim to the sector by bribing the Corellian Diktat. Upon Grunger's arrival in the Corellian system, close to the planet Tralus, Pitta assumed control of a Torpedo Sphere siege platform and initiated the annihilation of Grunger's armada. Unwilling to concede victory to Pitta, Grunger rammed the Aggressor directly into Pitta's Torpedo Sphere, an act that resulted in the destruction of both vessels. Both Grand Admirals, who were still aboard their respective flagships, perished in the resulting collision.
Roek, a cunning admiral, originally commanded the Super Star Destroyer, utilizing the Aggressor as his flagship. Later, Grand Admiral Josef Grunger, one of the first Imperial warlords to break away following the Battle of Endor, commandeered the warship. Driven by ambition and loyalty only to himself, Grunger seized the Aggressor to serve as his personal command ship, leading a substantial force consisting of Star Destroyers and other vessels from it. The Grand Admiral's ambition was to conquer Imperial Center using his armada, with the Corellian system serving as a staging ground. However, it was within that system, during the Battle of Tralus, that Grunger, facing defeat, made the decision to ram the Super Star Destroyer into Grand Admiral Pitta's Torpedo Sphere, resulting in the deaths of both commanders and the destruction of their respective flagships.
The Aggressor was initially referenced within the article titled "Recon & Report: The Journey to Coruscant," featured in the second issue of the Star Wars Adventure Journal, which was published in 1994.
- " Recon & Report: The Journey to Coruscant " — Star Wars Adventure Journal 2 (also reprinted in The Best of the Star Wars Adventure Journal, Issues 1-4) (First mentioned)
- " Who's Who: Imperial Grand Admirals " — Star Wars Insider 66
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