The Eclipse II was developed around the same time as the first Eclipse, in 0 BBY–0 ABY. Unlike the first Eclipse, however, the Eclipse II was developed directly above Byss. Similar to its sister ship, the Eclipse II was also delayed in completion due to Palpatine's demise.
It served as the flagship of Emperor Palpatine after the destruction of the first Eclipse. The Eclipse II transported Palpatine to the Sith world of Korriban, and later become the focal point of the Battle of Onderon, where the New Republic attempted to capture the Emperor.
Eclipse II was ultimately destroyed over Byss, after the astromech droid R2-D2 took control of its computer banks and set the ship on a collision course with the Galaxy Gun. As it crashed into the orbital cannon, a projectile from the Galaxy Gun ejected and was pulled towards the planet below. In the ensuing explosion, both the remnants of the Star Dreadnought and the superweapon were destroyed. Its destruction alongside Byss also resulted in a massive amount of deaths among the royal guards, leaving only a handful left in existence, including Kir Kanos and Carnor Jax.
- Star Wars: Empire's End (First appearance)
- Empire's End audio drama
- Crimson Empire 3 (In flashback(s))
- Star Wars: Behind the Magic
- The Essential Guide to Planets and Moons
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- The Official Star Wars Fact File 33 (EMP2, The Emperor's Royal Guard)
- The New Essential Guide to Weapons and Technology
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- Star Wars: The Comics Companion
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- Star Wars: The Official Starships & Vehicles Collection 31
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