* BizarroEpisode: The nature of the crossover caused a few for some titles that tied in to it. Many Marvel comics did an issue set in the House of M reality that had little or nothing to do with those books' ongoing storylines. Lampshaded in an issue of ''ComicBook/{{Thunderbolts}} released after the crossover where the recap is the Purple Man -- describing himself as a writer -- complaining that his story was abruptly interrupted by something very unimportant.
* CompleteMonster (''Civil War: House of M'' miniseries): In this timeline, before ComicBook/{{Magneto}} takes over the world, [[MadScientist Dr. Bolivar Trask]] is the Vice President under UsefulNotes/RichardNixon. Trask is also the director of the Sentinel program and a major player in an [[FantasticRacism anti-mutant]] conspiracy. Trask has set up forced labor camps across America that use mutants as slave labor. When Magneto assassinates anti-mutant activist Graydon Creed, Trask uses that as an excuse to send a strike force to Genosha to kill Magneto. Under Trask's orders, Bucky Barnes threatens to blow up key facilities in Genosha, including a hospital, if Magneto does not let Bucky kill him; Bucky kills Charles Xavier in the process. After killing Bucky, Magneto goes to the White House for revenge. Trask uses this as an excuse to launch a nuclear strike against Genosha. When Blackbolt disables the nuclear missiles heading to Genosha, Trask considers [[NukeEm nuking]] the Inhumans' city of Attilan as well. When confronted by Magneto, Trask sends his special Theta Sentinels to kill Magneto, not caring whether he or his SHIELD subordinates die in the process.
* SugarWiki/FunnyMoments: Wolverine waking up in the ''House of M'' reality to find a strange redhead looming over him, which quickly turns out to be Mystique, who grumbles when Logan attacks her: "it's ''your'' redhead fetish!"
* SugarWiki/HeartwarmingMoments:
** Captain America's reaction to seeing Hawkeye's uniform hung up on the wall of the derelict Avengers Mansion, next to a newspaper clipping reporting on Clint's death. He immediately realizes what it means, and smiles.
** At the end of Fantastic Four issue 3, the It is found by a couple of members of the Human Resistance. When he reveals he WasOnceAMan, they decide to bring him into the Human Resistance and it ends with him encountering Alicia Masters who tells him he's in good hands with her.
* HarsherInHindsight: Angela Del Toro, the then-current White Tiger, is part of Luke's team, but doesn't do anything before being killed by a Sentinel. Then, a few years later Angela got [[DroppedABridgeOnHim a bridge dropped on her]] for real.
* HilariousInHindsight: Spider-Man asks Doctor Strange to erase his memories of the alternate reality, only to be told that he can't do that with his magic. Two years later, ComicBook/OneMoreDay had Doctor Strange cast a spell that erased the memories of ''every person on earth'', making it so that nobody remembered Spider-Man unmasking in ComicBook/CivilWar2006.
* MemeticMutation:
** "No more [X]"[[labelnote: Explanation]]Replacing Wanda’s “No more mutants” line with literally anything.[[/labelnote]]
** Bendis's assertion that the series would "break the internet in half" took a life of its own as short hand for when a creator oversells the impact of an event.
* NeverLiveItDown: Among her detractors, Wanda wiping out 99% of mutantkind in a fit of grief-induced madness is never going to go away.
* OlderThanTheyThink: So, a madman got reality warping powers, AndThatsTerrible. All reality bends to the madman's insane thoughts. Oh, wait. Did you think that House of M was a nightmare? Because, in the Batman vs. Hulk crossover, ComicBook/TheJoker got that power. See a free preview [[http://www.marvunapp.com/Appendix3/earthcrossoverall14.jpg here]] and [[http://michelfiffe.com/columns/jose_luis_garcia_lopez/images/04.Joker.jpg here]].
* {{Padding}}: Some critics and fans believe the event suffers from an excessive amount of filler scenes, and accuse Bendis of overusing [[DecompressedComic decompressed storytelling]]. The majority of the criticism is directed at issue #2, which is entirely dedicated to showing mundane events from the Avengers and X-Men's personal lives, slowing down the plot progression to a crawl.
* TheScrappy: Layla Miller was not well-liked by the readers when she debuted in ''House of M #4''. People thought Layla was there for the sake of being a plot device by unlocking many characters' "memories" and the readers accused Layla as a SpotlightStealingSquad when the readers wanted to know what happened to other more important characters not shown in the panels. To make it worse, after Layla unlocked many people's memories, she then disappeared from the story and was not mentioned for a long time. After the series concluded, Layla became a main character in the relaunched ''ComicBook/XFactor'' series, where the character was completely reworked.
* StrawmanHasAPoint:
** While Emma Frost's argument in the first issue is pretty callous ("kill Wanda"), she does point out that if the population of the Marvel Universe, known for their knee-jerk reactions to just about ''everything'', found out that a Mutant killed several Avengers, they'd take it poorly and try and wipe out mutantkind.
** Nobody actually answered Spider-Woman[[spoiler:'s Skrull doppelganger]] why it was necessary to set the world back, although the whole "humans are a ''persecuted'' minority" thing would presumably be enough to convince the heroes to change it back. They also make the case that this reality is literally at the whims of a psychotic RealityWarper, but such is the case of the Franchise/MarvelUniverse every other week.
* TearJerker:
** When ComicBook/SpiderMan learns that setting the universe right would mean [[spoiler:losing both the resurrected Gwen Stacy and the young son they had together ''forever''. And don't get started on Uncle Ben.]]
** Before that, the two page spread of the notable events of Peter's life coming back to him, including the deaths of Uncle Ben & Gwen Stacy. Going through all that again, ''in mere seconds'', and [[spoiler:with Uncle Ben & Gwen asking if he's alright as he regains his composure?]] Peter immediately takes off. The other heroes all have looks on their faces that suggests that they're thinking that restoring Peter's memories wasn't the best decision, but Luke Cage sums it up perfectly.
--->"That was damn awful."
** Hawkeye. He's alive in this world, he's dating Mockingbird... But then he loses her when she goes to Wakanda, gets his memories back and knows that, not only has she left in House of M, she's believed to be dead at that point. Him demanding to know why Wanda killed him is heart-breaking.
** Luke Cage trying to call Jessica Jones, his fiancée in the real world, only to get through to an answering machine message of her & Scott Lang. Cage then asks if Spider-Man tried to contact Mary Jane, but Spidey admits he didn't because she's better off without him, pointing to her flourishing career. When Cage tries to reason that it's not true, Peter simply states "But we're not, and she is."
* TheWoobie:
** Spider-Man, after his memories are restored and he realises [[spoiler:that Uncle Ben and Gwen Stacy should be dead.]] It's even noted with Shadowcat noticing that Spidey's not making his usual sarcastic remarks, and is just silently hunched over in the corner. And then in the epilogue, he desperately pleads with Doctor Strange to [[spoiler:erase his memories of the resurrected Uncle Ben & Gwen Stacy, and his young son Richard.]] By the end of it, you just want someone to give the poor guy a hug.
** For that matter, Doctor Strange emerges from the event looking and sounding somewhat shattered and saying his failure as Sorcerer Supreme is to blame for it all.
** Hawkeye. He finds out that he was killed by a friend and can't handle it, then he's killed again, and then he's brought back at the end. The worst part is that he takes off alone again when he's brought back at the end. He's with Mockingbird in House of M -- who chooses to leave for Wakanda. When he gets his memories back, he discovers that she's dead in the real world.
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