Even with his starfleet of thousands of Imperial Class Star Destroyers, and the monolithic Super Class Star Destroyers, the Emperor felt that the Imperial Navy lacked a certain amount of versatility to combat the rebels. Consequently, the Empire Class Star Destroyer was commissioned. Slightly larger than the older Imperial Class Star Destroyers, it was initially intended for development as an all-purpose heavy cruiser. Based on the plan of the successful ISD design, the ESD had one major difference. A large segment was cut out of th triangular front, in order to place a well-protected, and more efficient fighter bay. Through numerous battles with the rebels, it was discovered that the old "underbelly" style fighter and docking bay did not deliver combat ships into battle fast enough, so in addition to the ventral bay, the frontal one was added. This increased effectiveness in battle, and allowed faster delivery of troops and equipment for ground operations.
The project was doomed to failure after the Rebel strike against the first Death Star. Afterwards, the Emperor deemed it too costly do develop another large starship, and instead diverted funds to the construction of standard ISDs. Even though the program was cut short two prototype ESDs were built, and stored at the shipyards. Since that time the ISD has become outdated and the Empire needed a more reliable and versatile ship to combat the New Republic. The Empire pulled together most of its funds relying on this vessel to support their dwindling numbers. Now the ESD serves as the standard capital ship of the Empire, however the older model Imperial and Victory Class are still used in some remote sectors.