Barbatos

As a hero in Gotham City, Batman trained many pupils, including Duke Thomas and Nightwing. At some point, he was cast back in time, where he caught the attention of the dark god Barbatos. Barbatos planned to use Batman as his entry point into the multiverse, and centuries later he did just that. He and his minions, such as the The Batman Who Laughs, besieged the universe using Batman. Eventually, Batman and the Justice League donned armor made of Element X to battle him, only to find that the armor was a trap placed there long ago by Barbatos. The armor destroyed the heroes, and remade them into horrible beasts. Bruce, however, was more than a mere monster, becoming a manifestation of Barbatos himself.

For two years, the new Barbatos led his Dragons of the Bat in a war on the multiverse, causing a cosmos-destroying "Deathwave". Upon returning to their original homeworld, now called "Earth-Metal", they encountered Batman's former pupil Duke, who had traveled into the multiverse to try and stop the Deathwave. Duke rallied a new Justice League, composed of the world's few remaining heroes, who defeated the Dragons at the cost of their own lives. Barbatos battled Duke head-on, and while he proved much stronger physically, neither his power nor his cunning words could stop his former trainee. Duke teleported inside Barbatos, finding what remained of Batman's original body, and cut it free from the rest of the beast, killing him. It was too late, however, as Duke had only moments to fashion the dragon's skin into armor before the Deathwave collapsed existence itself around him.