The 3 years Azzarello was on the book, the overall plot was chasing Zeke and defeating the First Born. It's not like there were different toned stories like in King's current run or different villains every few issues like in Perez or Cloonrad's runs so it's difficult for me not to think of Azzarello's run as not 1 big long story. I guess if you insist on me carving out an issue or two from it, I'd say the one where Diana crunches Orion's junk and threatens to castrate him.