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.
The Youtini Expanded Universe Ranking system is a 1-5 scale that ranks EU book quality, difficulty, and importance. Books closer to Level 1 are easier to read and understand, more important, and of higher quality.
Alderaan holds a secret—a secret on which the future existence of the Jedi depends. Under strict instructions from the Emperor, double agent Ferus Olin must both uncover this secret and protect it. What he discovers raises dark questions from his own past—and puts him in direct conflict with another former Jedi…the sinister Dark Lord of the Sith, Darth Vader.