The Mega-class Star Dreadnought, alternatively referenced as the Mega-class Star Destroyer, the Mega Star Destroyer, or the First Order Mega-Destroyer, represented a class of Star Dreadnought that was operated by the First Order during their war against the Resistance. It was considered to be the most massive vessel ever created in the history of the galaxy.
The Mega-class Star Dreadnought had a width exceeding 60 kilometers, and a length of nearly 13 kilometers. It had the capacity to transport six Resurgent-class Star Destroyers within the rear section of its wings, in addition to two more located internally.
It was equipped with approximately 32 sublight engines, along with a hyperdrive system. It also contained a hyperspace tracker, similar to those found on other starships. Its carrying capacity was 2,225,000 individuals, encompassing stormtroopers and officers. The vessel featured a throne room intended for Snoke, the Supreme Leader of the First Order, alongside numerous automated laundry facilities.
Furthermore, the warship was armed with powerful turbolasers, anti-ship missile launchers, and tractor beam projectors. The vessel transported a substantial quantity of diverse military vehicles, including dropships, All Terrain Armored Transports, All Terrain Scout Transports, and All Terrain MegaCaliber Six walkers.
The only Mega-class Star Dreadnought within the First Order Navy was the Supremacy, which served as the flagship of Supreme Leader Snoke and also acted as the de facto capital of the First Order. The Supremacy sustained significant damage while assaulting the Resistance fleet when Vice Admiral Amilyn Holdo collided with it at near lightspeed utilizing the heavy cruiser Raddus, bisecting the Dreadnought and resulting in the destruction of several of its accompanying Resurgent-class Star Destroyers. Despite the extensive damage, the Supremacy was still operational, but it was subsequently abandoned and intentionally destroyed by the First Order Navy because it was too severely damaged to be repaired.