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.
In the eight years since the fall of the Empire, Luke Skywalker has trained a new group of Jedi Knights, among them the Dathomir Witch Kirana Ti, the sky-hermit Streen, the scholar and lore-master Tionne, and Luke's greatest student, the brash Kyp Durron. Once trained, a Jedi must go where he is needed, to defend the New Republic and use the Force to help those in need. And on the harsh world of Corbos, help is desperately needed after mining excavations awaken something ancient, powerful...and hideously evil!