* R-D. There is nothing freakier than seeing what amounts to a clone of Dorothy(an emotionally subdued but otherwise nice girl), SlasherSmile 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 4 if memory serves, the very creepy one that tries to [[MindRape "make friends" with Dorothy through unorthodox means.]] Nightmare fuel indeed.
*** Made even worse in one episode of the second season: [[spoiler: 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, [[spoiler: "Is that thing Big O's archetype?"]] It's surprisingly creepy for being a robot, the megadeus equivalent of a fast zombie.
* [[spoiler: Alan Gabriel's demise. '''YE GUILTY'''.]]
* Big Venus. Basically resembling Big O but with its colors inverted and sporting a large [[SlasherSmile grin]], it has the ability to alter and manipulate memories and reality itself.