After a fight with Brainiac, Superman gets a call: Lana Lang had been in a car accident, causing her to prematurely give birth. Confronting his old friend, she begs him to save her child's life. At the same time, the Justice League is called in to the scene of a disaster, only to find themselves face to face with... Doomsday?! But, he was shunted into the end of time! How did he survive?!
This series provided these tropes:
- All Your Powers Combined: With Doomsday's strength augmented by Brainiac's intelligence, Superman is facing a true nightmare, as his most physically powerful and intelligent foes come together to create a seemingly unstoppable opponent that combines their strengths with none of their weaknesses.
- And I Must Scream: Doomsday's fate, trapped between four constantly teleporting tubes. They were meant to stay that way for centuries, but Doomsday was forced to be freed due to the events of Our Worlds at War.
- Back from the Dead: Doomsday, rescued from the End of Time. As well, Brainiac, who survives his own body dying.
- Batman Gambit: How Superman ends up beating Brainiac and trapping Doomsday for good; he provokes Brainiac-in-Doomsday into attacking him directly so that he can use the psi-blocker he used in their last fight to 'exorcise' Brainiac from Doomsday, and then lures Doomsday to the moon anticipating that he would make a beeline for the Watchtower.
- Book Ends: The Doomsday Wars effectively plays itself in reverse from The Death of Superman: the story begins with Superman fighting someone in Metropolis who is killed (Brainiac in this case), the Justice League rallies around Superman near the end and the story ends with Doomsday being imprisoned and Superman flying off to save another day.
- Clark Kenting: When Pete rescues his son, he's electrocuted and knocked out. When he starts to come to, he sees Superman in silhouette and mistakenly calls him "Clark", surprised that he followed him there. Superman runs with it and uses the moment to help mend fences between the two men.
- Chekhov's Gun: At the beginning of the story, Superman uses a psychic dampener to prevent Brainiac from controlling him. At the end, he uses it to drive Brainiac out of Doomsday's mind.
- Curb-Stomp Battle: The Justice League featured here was the one built up by Grant Morrison, with the ones answering the call comprised of Martian Manhunter, Wonder Woman, Kyle Rayner Green Lantern, the Wally West version of The Flash, the New God Orion, Plastic Man and the Huntress. Brainiac-controlled-Doomsday still wrecks them, though it's not as bad as the stomping the last League to face Doomsday got.
- Empty Shell: Despite Brainiac hijacking Doomsday's mind, Brainiac realizes that its animalistic nature makes him tough to control, thus he needs a new, permanent home.
- Flashback: The mini-series jumps between the present day and an event in Clark's past where Clark accidentally caused his family's cows to be killed during a terrible snowstorm and the aftermath.
- Friend-or-Idol Decision: While talking to Lana, Clark gets the call from the Justice League needing his help. Lana begs him to help save her son. He opts to stick with Lana, which confuses the League when Doomsday kicks their collective asses.
- Genetic Engineering Is the New Nuke: Brainiac intends on creating a brand new body by stealing Lana's baby, healing him, then infusing him with Doomsday's DNA, allowing him to create a brand new perfect body, with Doomsday's raw power but lacking even the feral mind of the original.
- Good Feels Good: In the story's conclusion, Clark admits to himself that there are times when he doubts whether he does any good being Superman, because the fight goes on and on and on... then he looks at Lana and Pete, crying over their rescued baby son, and mentally kicks himself for being such an idiot.
- Grand Theft Me: Brainiac does this to Doomsday once his body fails, although he notes that he can only contain Doomsday's feral mind for so long before Doomsday's basic strength of will will force him out.
- It Only Works Once: Brainiac's powers had grown way too strong for his fragile flesh and blood body. He attempts to make a new body by taking DNA samples from Doomsday and integrating the sample into a captured infant, but when that fails, he's forced to hide in a robotic body that he can never leave again
- Jerkass: Pete Ross. Though, this is incredibly understandable, as his wife has just called in Clark, then called in Superman, to try to save their son, then Superman loses his son to Doomsday-Brainiac. The man is incredibly helpless here.
- Loophole Abuse: As it turns out, this trope is how Doomsday survived his death at the end of Hunter/Prey: time was still mutable due to the events of Zero Hour: Crisis in Time!, allowing Brainiac's flunky to snatch him up before Entropy swallows him.
- Mistaken Identity: When Brainiac takes possession of the device holding Pete and Lana's son, he believes that the child is someone majorly important.
- Nice Job Fixing It, Villain: Brainiac attempting to use Lana and Pete's son as his new body ends up saving the child, bringing him to full term.
- No One Could Survive That!: Superman's initial battle with Brainiac has the madman immolated by an exploding bus. Superman's more than certain Brainiac didn't survive that. He was almost right.
- Papa Wolf: Pete Ross, finding his way to Brainiac's lair, knocking out his lackey and saving his son.
- Took a Level in Badass: Initially it appears that Doomsday has 'just' become intelligent, before it's revealed that he's actually 'possessed' by Brainiac's consciousness.
