What is the Knight Hammer? 
A black Super Super Star Destroyer that is eight kilometers long, can carry a crew of up to a hundred thousand, and is plated with stealth armor which gives it a black appearance.

History: 
The Knight Hammer was built by Superior General Delvardus and was turned over to Admiral Daala after his death.  The ship was originally named Night Hammer because of its coloring. But, Admiral Daala renamed the ship when she decided to make Yavin IV, home of the Jedi Academy, the first planet she attacked with it, proving that she did indeed have a sense of humor.

Catastrophic Destruction: 
The Knight Hammer was destroyed during the battle over the Jedi Academy. The former Jedi, Callista, flew a stolen TIE fighter up to the ship, convinced the crew to clear a docking bay for her due to a "leaking engine core", and went from ship to ship in the docking bay, setting all their missiles to go off in a huge chain reaction.  However, even that did not completely destroy the mighty ship.  It was left dead in space, and was pulled to its final destruction by the powerful gravity of the gas planet Yavin.