YMMV / The Super Dog from Krypton

• First Installment Wins: By the 1990s, DC did not want multiple Kryptonian characters around, not even dogs, so they retconned Krypto out and tried to replace him with a common Earth dog who was named "Krypto" by a Superman fanboy...and who never became popular in-and-out-universe, only making a handful of appearances before being sent to comic-book Limbo, completely forgotten and replaced by the returning original Krypto.
• It Was His Sled: Krypto's identity and nature was be a surprise in 1955. Nowadays, most of the people who know about Superman are at least aware that he has a Kryptonian pet dog called Krypto.
• Unintentionally Unsympathetic: Superboy is meant to be understandably angry when he berates Krypto, since Krypto had been making trouble for him and jeopardizing his secret identity, but he comes across as unlikable since he is complaining about his pet dog being "super-trouble" instead of "super-fun", as if Krypto was a toy instead of a living creature who he is responsible for (and who spent fifteen years trapped in a rocket thanks to his father).
• Vindicated by History: By the 1980s, DC regarded Krypto's origin story as another instance of convoluted Silver Age silliness which should go. By the early 2000s, though, it was decided to bring the character back, giving him a less contrived origin....which was actually more convoluted (instead of being used by Jor-El to prove his rocket, which was blown off course and took over fifteen years to reach Earth, Krypto was a dog from a false Krypton), so it was retconned out and replaced by the original story shortly after. Superman's 2011 reboot tried to "update" Krypto's origin again (having him to be sucked into the Phantom Zone before Krypton's explosion), but nobody particularly cared about that story, so DC retconned his first appearance back into canon.

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