When Alan Moore returned Miracleman (for clarity's sake, I'm going to refer to everyone by the "Miracle" name, even though in the early parts of this story, they were still called Marvelman, etc.) to comics, it was to a world that had vastly changed since Michael Moran was a young man and first turned into Miracleman upon saying the magic word "Kimota." This was shown quite clearly when Miracleman encountered his former compatriot, Kid Miracleman, who had gone mad with power over the years and was now basically a sociopath. After a brutal fight, Kid Miracleman accidentally says his magic word and reverts back to his alter-ego, the 13 year old Johnny Bates. Bates has no memory of his actions as Kid Miracleman and ends up in a state of catatonic shock.
After a good deal more issues of adventures dealing with the return of Miracleman, including the reintroduction of Miraclewoman and introduction of the benevolent teleporting aliens, the Warpsmiths, Kid Miracleman returned.
While Miracleman and Miraclewoman are busy in outer space, tragedy strikes back on Earth. The young Johnny Bates is now living in a group home, where other kids mercilessly pick on him. That was bad enough, but when one of the other kids goes so far as to rape Johnny, Johnny just snaps and turns back to Kid Miracleman and in “Miracleman” #15, one of the goriest superhero fights ever takes place.
Artist John Totleben goes into great detail depicting what it would look like if a superpowered sociopath just went nuts in London. Body parts are literally raining from the skies. When Miracleman, Miraclewoman and the Warpsmiths return, they are in for a dramatic battle that would end with even more property destruction and civilian deaths. Alan Moore is intent on showing what would be the case if superheroes actually fought each other in the "real world," particularly a psychotic being like Kid Miracleman. It is not a pretty sight.
After a pitched battle, Miracleman realizes that Kid Miracleman is better prepared and is stronger than all of them. Ultimately, it is the thinking of a Warpsmith that saves the day. All the heroes are stymied by Kid Miracleman's personal force field. However, one Warpsmith comes up with the idea of teleporting a piece of wreckage past the protective force field, into the body of Kid Miracleman, forcing Kid Miracleman to transform back into Johnny Bates.
At this time, Miracleman feels he has no other choice but to kill Bates, which he does, ending the threat for good, but not before Bates manages to kill one of the Warpsmiths, and not before the city of London was absolutely decimated, both in terms of casualties and property damage. And Alan Moore had yet another standout comic book story.