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* Sweet, soft-spoken Ayano ''punching Misao in the face'' in Chapter 3 when under the influence of a Demon Brand, and screaming that she hates her and never wants to see her again... brrr.
* The flashback to Kyoko's death, at the very end of the final battle with Vittoria. It immediately establishes just how much the war cost, and just how powerful she was.
** In the same chapter, this is followed by a chilling scene in which [[Manga/PuellaMagiKazumiMagica Nico]] reveals how many surviving Puellae Magi there are on Earth: ''four.''
* In Homura's world, the event that set off the war. Less than ten steps from safety, a mortally-wounded horde of Demons lets off one last, desperate attack: a lightning bolt that kills Tsukasa instantly, [[KilledMidSentence in mid-sentence]], in full view of Kagami. All the work the combined Puellae Magi put into protecting them both, and they failed ''literally'' at the last second.
* Kagami's [[DespairEventHorizon fall]] and transformation in Chapter 9, and [[Manga/PuellaMagiKazumiMagica Kazumi's]] sudden death immediately after. Vittoria reaches through her shield, drains her [[SoulJar Soul Gem]], and she's just... ''gone''.
* The Third, which takes the form of a giant, rabid, emaciated three-eyed dog with a stomach filled with maggots,]] is terrifying enough already, but it gets turned UpToEleven when it ''[[SwallowedWhole swallows Kagami whole]]''.
* Konata being corrupted into a BrainwashedAndCrazy red monk by Jiovanni.
* '''Chapter 16'''. Desideria ''brutally'' {{Mind Rape}}s Homura, recounting a twisted, half-truth version of the events that led her to Kagami's world... while also using her powers to ''literally'' [[RapeIsASpecialKindOfEvil rape]] [[FantasticArousal her Soul Gem]]. It's played for all the stone-cold horror possible, and leaves Homura in a near-catatonic state.
* Remember the Yuki cosplayer in that one episode of ''Anime/LuckyStar'', the one who worked at Konata's CosplayCafe? She gets ''flayed to death'' by monstrous crows in Chapter 20, leaving a completely skinless corpse behind.
* In ''My Sunshine'', Mami has her memories slowly eaten until she is basically reduced to an infantile state of mind.]] It's both scary and heart-wrenching.