The Big O/YMMV
- Complete Monster: Alan Gabriel is a terrorist, Serial Killer and thrill-seeking psychopath who leads the group The Union. Obsessed with hurting others for fun, Gabriel gleefully carries out his group's assassination missions, especially targeting sentient cyborgs to hurt them the most. Regularly organizing destructive terrorist attacks on Paradigm City, Gabriel betrays The Union for Alex Rosewater, killing his former comrades before hunting down heroine robot Dorothy and trying to torture her to death to mock the hero Roger Smith with it. Growing bored with working for Rosewater, Gabriel is given his own giant robot, a Megadeus, and proceeds to attack Paradigm City, intending on slaughtering and massacring everyone he can.
- Eugene Grant, from "Missing Cat", is a truly despicable Mad Scientist convinced that he is a god due to his recent discoveries in transmutation. To constantly improve his alchemic transmutations, Grant kidnaps innocents by the dozens and transforms them into pain-stricken abominations that he keeps alive and on display for no particular reason. When many of his old partners abandon him because of his depravity, Grant has one mauled by one of his monsters, and kidnaps two of his former compatriots' son Roy before turning the boy into a cat, following this up by murdering said couple in front of their son. Grant proceeds to transform Roy into a monstrous chimera, then sics it on Roger Smith while he holds Smith's partner Dorothy at gunpoint, ordering Roy to destroy first Smith, then all else in his path. Despite being a Villain of the Week, Eugene Grant handily stood out as the most wicked and irredeemable monster in the series alongside Alan Gabriel.
- Fan-Preferred Couple: Roger/Dorothy. In the English dub, this is made even more textual byRoger in season 2 by saying to a then deactivated Dorothy that if they had met in another time and another place and if Dorothy were human, then it would have been very likely that they would have fallen in love.
- Genius Bonus: The trippy opening sequence features newspaper clippings in the background, announcing veridical events such as the death of the 1950s jazz musician, Lester Young.
- Germans Love David Hasselhoff: The series wasn't very popular in its native Japan. America, on the other hand, liked it so much it got a second season designed specifically with Western fans in mind. Appropriately, This is exactly what the designer of the series wanted.
- Hilarious in Hindsight: Alan Oppenheimer voicing Norman is Season 2, who as noted above is an Expy of Alfred. Opperheimer went on to voice Alfred's appearance in the movie Superman/Batman: Public Enemies.
- The series has often been described as "Batman...WITH MECHS". In Batman the Brave And The Bold, Batman himself does indeed have a mech.
- On Family Guy, Adam West, famous for playing Batman in the 1960's Batman TV show, gets the line, "Oh my god... I'm a tomato!" Strange Minds Think Alike?
- Memetic Mutation: It's anime Batman!
- Narm: "I'm one of the tomatoes!"
- Narm Charm : The same line to some people.
- Nightmare Fuel: R-D. There is nothing freakier than seeing what amounts to a clone of Dorothy(an emotionally subdued but otherwise nice girl), Slasher Smile and all, screaming maniacally at Roger just as she's about to put a bullet through him. If nothing else, that face...
- Also a 'face scare' is Beck's horrifying visage in the dark in his last appearance within the manga.
- Another is in the finale, with the eerily grinning and skeletal Big Venus.
- There's also the Megadeus that Schwartwald finds during Episode 6 if memory serves, the very creepy one that tries to "make friends" with Dorothy through unorthodox means. Nightmare fuel indeed.
- Made even worse in one episode of the second season: While being repaired, we see the Big O without its faceplate. It has the exact same head as the Megadeus from that episode. In other words, that thing is what the Big O looks like under all that armor.
- Roger asks as Schwartzvald is standing on it's shoulder, "Is that thing Big O's archetype?" It's surprisingly creepy for being a robot, the megadeus equivalent of a fast zombie.
- Nightmare Retardant: Schwarzwald is significantly less scary/intimidating when he looks uncannily like Getter 2 with all those bandages.
- Tear Jerker: The end of Episode 10 has a pretty major one. Throughout the episode, Dastun has flashbacks to the movie he watched as a child, of the man who shoots the woman he loves at a pier. At one point, he even sees apparently the same woman holding a red balloon. At the climax of the episode, he confronts her at the pier in a real Generation Xerox moment, and re-enacts the final scene of the movie. Then at the very end, there is one final flashback, of Dastun as a child watching the movie, with a young Sybil Rowan, who is holding a red balloon.
- And toward the end of season 2, when reality itself seems to be falling to pieces, Dastun comes across a poster for the movie, advertising Dan Dastun as the male lead--and then he promptly runs into the child versions of Sybil and himself. Which means that, as a child, he watched a movie that he had already starred in as an adult, and then later plays out a real life version of a scene from said movie with a woman who may or not have been the actress from the film. I don't think I've ever known something to be so tear jerky and mind screwy at the same time.
- Too Cool to Live: Schwarzwald, the only Megadeus pilot that ever gave Roger any real trouble. And the only proper Megadeus pilot other than Roger. Alan was deemed unworthy and eaten by the revived Big Duo, and Alex's Big Fau shut down on its own accord before 'merging' physically with him.
- Villain Decay: The anime version of Beck, though considering many people found his Crazy Awesome Laughably Evil to be amusing as hell, it's not necessarily a bad thing.
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