BBY/ABY is used to position items along the Star Wars Timeline. BBY refers to Before the Battle of Yavin. ABY refers to After the Battle of Yavin. The Battle of Yavin in Episode IV: A New Hope occured in 0 BBY/ABY.
This tale of treachery and genocide leads up to the events of the record-breaking blockbuster Star Wars: Episode III – Revenge of the Sith. Before his short battle with Obi-Wan Kenobi, the latest Star Wars supervillain took on an entire alien species!
On a rescue mission to Vandos, Padawan Flynn Kybo and his master T'chooka D'oon come face-to-face with General Grievous, one of the leaders of the Separatist army. After Grievous kills Master D'oon, Kybo goes to the Jedi Council with a plan to take the depraved general out immediately. But when the council rebukes his plans for vengeance, Kybo decides to take matters in his own hands. Seeking out others who feel the same as himself, he sets out to stop the Separatist killing machine before more Jedi lives are lost. Meanwhile, Grievous hijacks a transport ship, and its precious cargo may give him a horrible advantage over the Jedi that they would never expect. For now, his sights are on the planet Gentes—and on taking its Ugnaught population and mining facilities as trophies of war!