Two Rebel squadrons (Blue and Gold) were equipped with RZ-1 A-wing interceptors, updated versions of the R-22 Spearhead piloted by Keyan Farlander on his reconnaissance mission in the star system about three years earlier. The other two squadrons (Rogue and Red) flew T-65 X-wing starfighters armed with a pair apiece of advanced proton torpedoes and given the role of attacking the Victory-class Star Destroyer. All four squadrons entered the system about a minute out of warhead range from the Formidable, which began locking onto the starfighters with its concussion missile launchers and shooting missiles at them from out of range. The Victory-class Star Destroyer also deployed its complement of TIE/IN interceptors, the pilots of which might have judged the opposition to be too fierce and called for reinforcements from Tau Squadron, which was on standby in Assault Gunboats nearby.
As the Formidable was well equipped to counter starfighter attacks and its TIE pilots attacked with ferocity, to say nothing of the meager half-load of warheads allotted to the Rebel strike force, it is probable that at least one flight group from Green Squadron, another X-wing outfit based in the sector, arrived on-scene to assist in the attack. Eliminating the Formidable was critical to the Alliance, but the Rebels could not afford to lose more than two-thirds of their starfighters in the engagement. It was the task of the Formidables TIE interceptors to inflict heavy casualties and drive the Rebels into retreat, or at least to stave off the destruction of their command ship until the Imperial Nebulon-B frigate Fury could arrive to render assistance.
The Battle of Delalt was apparently the final engagement of Operation: Clean Sweep.
As players can participate in the mission "Attack on Victory-class Star Destroyer Formidable" in the computer game Star Wars: X-Wing vs. TIE Fighter on either the Rebel or the Imperial side, both sides have conflicting mission objectives, and victory is not essential to access the next set of missions, the battle itself is considered canon but the canon outcome is unknown.
The ships listed in this article are those found in the battle Operation: Clean Sweep, using the default craft assigned to the player.
The Delalt system named in the mission description and briefings for "Attack on Victory-class Star Destroyer Formidable" is more than likely the Dellalt system featured in Star Wars: X-Wing. Both the Caluula sector and the unnamed sector containing the system featured in this mission were apparently either under Rebel Alliance control or contained a heavy Rebel presence during at least part of the time between the Battle of Turkana and the Battle of Endor, and it seems unlikely both that the Rebels would control two different sectors containing star systems with such similar names or that the game designers of X-wing vs. TIE Fighter, many of them carried over from the team behind X-wing, would intend the two to be separate systems.
The battle was evidently the last of the Imperial Operation: Clean Sweep, suggesting that the Formidable was in the system (which the Rebel mission briefing refers to as in "our Sector") conducting an offensive, as a Rebel counterattack after the Imperials had concluded the operation would probably not be considered to be its final battle (unless it was so decisive as to force the Empire to abort the operation, which seems unlikely even assuming the total destruction of the Formidable, the Fury, and all Imperial starfighters in this battle).