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.
Star Wars: Darth Vader by Kieron Gillen & Salvador Larroca Omnibus is a hardcover compilation that collects all 25 issues of the 2015 Marvel comics series, Star Wars: Darth Vader, written by Kieron Gillen with art by Salvador Larroca. It also contains the annual written by Gillen with art by Leinil Francis Yu. Three issues written by Jason Aaron for the Star Wars: Vader Down crossover are also included: Vader Down, Part I and Star Wars issues 13–14.