Doomsday is one of the most destructive villains in the DC Universe, capable of killing even seemingly unstoppable forces like Superman. That's what makes his equivalent within the Dark Knights such a potent threat. The Devastator is a version of Batman who has willingly transformed himself into a new version of Doomsday so he could be capable of bringing down anyone that threatened his world.
Now, we're taking a closer look at these two unstoppable forces to see which one is stronger, and if the Devastator's cunning mind would make him powerful enough to contend with Doomsday?
The Ultimate Lifeform
Doomsday was created by the committee of Dan Jurgens, Brett Breeding, Jerry Ordway, Louise Simonson and Roger Stern for the monumental "Death of Superman" storyline. The result of genetic manipulation to create the ultimate lifeform, the monster that would eventually become known as Doomsday carved a path of destruction across the universe. Doomsday has been built to survive almost any form of injury. Even if something does manage to kill it, Doomsday will be able to eventually resurrect itself, with a newfound resistance to whatever form of attack last stopped him.
Doomsday has proven itself to be one of the most destructive things in the entire DC Universe. It's tough enough to withstand energy attacks, including even taking Darkseid's Omega Effect straight to the chest and running through it. It's also proven to be strong enough to stand up against entire Justice League teams that have featured many heavy hitters in their own right. He's powerful enough to even stand up against heroes like Superman and Wonder Woman. He even briefly beat Superman to death (at the cost of its own life,) although both eventually returned to life.
Symphony Of Destruction
The Devastator is one of the Dark Knights, introduced for DC: Metal by Scott Snyder and Greg Capullo. Hailing from the dark multiverse, the Devastator is one of the corrupted versions of Bruce Wayne who came to the mainline DC universe as an agent of the dark god Barbatos.
This version of Batman was from Earth -1, a world where Batman and Superman worked together as some of the strongest heroes of their world. But when Superman became the monster the world always feared he could become, Batman took it upon himself to stop his old friend. He infected himself with a strain of the Doomsday Virus, transforming his body but retaining his mind. This Batman eventually killed his Superman and tried to do the same to the main continuity.
Devastator had more than enough strength to stand up to entire teams of heroes. He was even shown standing up to Superman, later even flinging Lobo into the sun during their fight. What makes Devastator particularly dangerous is the mind behind all that brawn.
Devastator was smart enough to learn how to transmit the Doomsday virus throughout all of Metropolis. He even concocted an airborne virus that exploded kryptonite out of the body of the Superman from his reality. Devastator was eventually killed alongside the other Dark Knights, except the Batman Who Laughs, which suggests that he may not have the sheer endurance and power of Doomsday.
Devastator has only appeared in one storyline so far, DC: Metal. Meanwhile, Doomsday has been something of a constant within the DC Universe since he first appeared in the build-up to "Death of Superman." Doomsday has had more opportunity to showcase his overwhelming power. He's been shown standing up to powerhouse heroes like Wonder Woman and Superman with ease, and often requires multiple people working together to bring him down. He's even been shown tearing through reality itself with his bare fists, once punching his way from Phantom Zone. The Devastator was strong enough to stand up to people like Supergirl and Lobo, but he hasn't been shown to be capable of going head to head with figures as powerful as Darkseid. like Doomsday has.
Doomsday lacks any real strategic mind, however. He's driven by a drive to kill anything and everything he can, and there's not much else that motivates him. Devastator may not have been shown being as physically dangerous as Doomsday, but his wealth of knowledge from being a former Batman makes him a threat that can bring down anyone if given the chance. If Doomsday were to fight against Devastator would actually probably play out like a Hulking version of the duels between the Batman and Superman: the question becomes whether or not Devastator has time to prepare. Because in a straightforward slugfest, Doomsday probably has the history and the advantage.