Source: toobusythinkingaboutcomics.blogspot.com

7. Batman/Spider-Man

Of course, the crossover you always wanted. This is actually the first of two Batman/Spider-Man crossovers, but if I'm picking one, I gotta go with the original.

In this story, Batman and Spider-Man are both having violent nightmares about the tragedies that turned them into the heroes they are. At the same time, experts in New York and Gotham have found ways to force Carnage and the Joker into being reformed. The experts meet up in Gotham to see who has done a better job, bringing their pet psychopaths in tow.

Carnage gets his symbiote out of dormancy and snaps the Joker out of his trance, initiating a team-up between the two. Spider-Man arrives in Gotham to help out with Carnage, but Batman wants none of it. Eventually, the two heroes team-up and take care of each other's nemesis, resolving their own personal issues as they do.

Some incredibly solid J.M. DeMatteis writing on this one, but the star turn is from artist Mark Bagley, who absolutely kills it here. So good.