8. Taken Down By Prometheus
There is a case to be made for Batman being his own greatest enemy. In Grant Morrison's seminal run on the Justice League book, he would test that theory quite literally with the introduction of Prometheus; a villain that is an evil version of Batman, only relying on a "quick fix" method of achieving human perfection rather than a lifetime of sacrifice and commitment.
Prometheus has a helmet that allows him to upload the combat abilities of the world’s greatest fighters directly into his mind. When he attacks the League's headquarters on the moon, he finds himself going one-on-one with Batman. The villain shakes the Dark Knight's confidence when he announces he has uploaded the skills of thirty of the world’s greatest martial arts masters and that the list includes Batman himself.
Although much of the fight takes place off-panel, the effect of seeing Green Lantern having a beaten Batman casually discarded at his feet by a sneering Prometheus is no less shocking.