What the?! There is a second Batman?!! Yes, there is.
A dazed Batman was teleported to a planet called "Zur-En-Arrh", where he met an extremely humanoid alien named Tlaon, who after spying on Batman decided to become this planet's "Batman". The Earth Batman discovered that on Zur-En-Arrh, due to elements (unknown to humans), he has "Superman-like abilities". The two "Batmans" teamed up to stop invader robots. This version of the Batman of Zur-En-Arrh had an "atomic-powered" "Batmobile" and a "Bat-Radia", that could "jam atmospheric molecules" to affect his enemies' equipment.
Dr. Simon Hurt made Batman insane: he forgot about his past life and was delusional (hence a Bat-Mite-like hallucination). Donning a colorful costume, he called himself "Batman of Zur-En-Arrh" tried to violently murder criminals. It was revealed the "Batman of Zur-En-Arrh" was actually a second personalty created to due exposure to Prof. Milo's gas. But, Batman's rationale (the Bat-Mite hallucination) stopped him.