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.
Following the defeat of the Second Imperium, Jacen and Jaina travel to the Alderaan system to retrieve a shard from Alderaan's core. However, they are not alone since they are being watched by Ailyn Vel, disguised as her father Boba Fett. In the past, Boba Fett had been an enemy of their father Han Solo and his daughter is continuing his legacy.