History YMMV / Up

* MoralEventHorizon: [[spoiler:Though Muntz crossed it offscreen before the plot when he started murdering tourists who came to visit Paradise Falls, he cements himself as being beyond redemption when he tries to kill Russell in cold blood.]]

* BaseBreakingCharacter: Charles Muntz. Has a more pointless Pixar villain existed to date? Discounting the age gap difference fact between Carl and he means he would long be dead before the movie's plot, the backstory reason for his StartOfDarkness is just absurd. Absurd enough that many feel his character is UnintentionallySympathetic. Some begged the question: did ''Up'' even need an antagonist? Some viewers felt the only villain of the story should've been Carl's own cynicism, stubbornness, and unwillingness to forgive failure. Muntz to them, should've been nothing more than the personification of Carl's inner demons projected onto a deceased man who was his [[BrokenPedestal former idol until discredited]].

* AlternativeCharacterInterpretation: Was Carl so fixated on getting his house to Paradise Falls that he never considered how he would survive there? Or did he intend to die there?

* RonTheDeathEater: [[UnwittingInstigatorOfDoom Construction worker Steve.]] Many fans think he deserved to be hit in the head by Carl due to the mishap with his mailbox, and blame him for causing Carl having to go to court and subsequently losing his house. What is overlooked however is the fact that Carl assaulted Steve, with him getting a gash in the head. Also Steve likely had no way of knowing how important the mailbox was for Carl. And he was genuinely trying to fix it and felt awful it had been damaged.

** Even Kevin the bird - remember when [[spoiler:her leg was hurt]]? [[spoiler:There's also an insane lunatic hunting her, has been hunting her constantly for decades, and is [[WouldHurtAChild putting her babies in danger]] with the intent to capture them and do who knows what else afterward]].

* HypeBacklash: Although nobody is going to call the film ''bad'', there is some debate on whether or not the film deserves the high praise it gets from critics and viewers, with some arguing that, aside from the [[SignatureScene "Married Life" montage]] at the start, ''Up'' is, more or less, a typical Pixar film. A ''good'' typical Pixar film mind you, but not one that deserves to be regarded as Pixar's MagnumOpus, when there are plenty of other films from Pixar that are as good, if not better than ''Up'' overall.

* JerksAreWorseThanVillains: As stated, Charles Muntz is a beloved villain. However the CorruptCorporateExecutive who wants to buy Carl’s house to bulldoze it for his construction field is a pretty hated character. It starts off simple enough, with just wanting to tear down Carl’s home, which while a low move, is basically just business, as he did offer Carl large sums to buy it. But any integrity goes out the window once Carl accidentally draws blood on one of the construction workers to protect his mailbox, which he promptly takes advantage of to sue Carl, who ends up losing the case, and in the settlement, sends him to a retirement home while taking his house away from him.

* TrueArtIsAngsty: While still a brightly colored, heavily optimistic film, it's considered one of Pixar's best movies and also one of the saddest.

** Since this film, "cone of shame" has become a popular term for the conical Elizabeth collar used on pets.

* CryForTheDevil: Muntz is a murderous bastard and FallenHero with how [[spoiler:Carl realizes immediately that telling him how to lure Kevin with chocolate is a bad idea, seeing his PsychoticSmirk]]. As we see in the opening, Muntz was once a respected scientist and explorer, who invented revolutionary technology. He then loses it all when scientists declare his bird skeleton a fraud and they strip him of his medals. Muntz vows to come back with a live bird, only for the task to take ''decades'' rather than a few months, with only talking dogs for company. That leads to GoMadFromTheIsolation where he kills anyone that comes, accusing them of wanting his bird. Carl tells Muntz sincerely that he and Ellie were the explorer's biggest fans, and he inspired them to come to Paradise Falls. Even as Muntz is hunting them down, Carl feels sorry for him because he knows the man was once a hero.

* LoveToHate: Charles Muntz. Sure, he [[SanitySlippage lost his mind]] all because of a bird but many fans couldn't help but root for the guy.