History DanganronpaTriggerHappyHavoc / TropesEToK

** Mondo mentions the color of Chihiro's sports clothing, in a situation where, aside from Celeste and Makoto (the former seeing Chihiro minutes before he was killed and the latter being the only person Celeste told this to before the trial), only the murderer would be able to know that information.
** In chapter 3, Celeste says that "We are going to die just like ''those'' guys" when, at the time, she had no way of knowing that there was a second murder victim.

* {{Irony}}: Celeste pruposes the "no leaving your room at nighttime" rule to the other students in hopes of preventing murders. In spite of this, all of the murders end up taking place at night. Celeste even breaks her own rule to kill two people too.

* KarmicDeath: Monokuma's punishments for the blackened students are specifically tailored to each of them: Leon is bombarded to death with baseballs, Mondo is strapped to a motorcycle and driven around a Globe of Death so fast that he turns to butter, and Celeste is set up to be burned at the stake...only to be crushed by a speeding fire truck instead. The exception is Alter Ego, who Monokuma only "executed" to toy with the surviving students.

*** Chapter 4 also counts even with Aoi's red herrings (and you don't learn about the suicide note until the end of the trial), as the locked room, Sakura's behavior (she's upset that her presence caused Aoi to get hurt and says she intends to solve the problems her presence is causing) and the poison powder on her shoes make it fairly clear she knowingly took the poison.
*** Chapter 5 subverts this, as some of the critical evidence is in the bio lab, which is not opened until the next chapter.
*** The identity of the Mastermind also breaks rule 10 of Knox's Decalogue by revealing that Mukuro and Junko are twin sisters (a reveal Junko herself calls cliched), although in this case it's a plot point that they ''aren't'' identical and Makoto notices this even though Mukuro is able to explain it away. Mukuro's identity is also foreshadowed by her gift likes; 'rations' and a 'god of war charm' aren't things you'd expect a fashion model to enjoy.

* EyeDentityGiveaway: [[spoiler:Compared to her fashion magazines, where they're much larger and more expressive, [[GyaruGirl Junko Enoshima]] is introduced with distinctively thin, almond-shaped eyes. She explains that the difference in appearance is because her pictures were photoshopped. As revealed in the final trial, the ''real'' Junko really does look exactly like the magazines. The "Junko" everyone met at the start was actually [[TwinSwitch her twin sister]], [[SociopathicSoldier Mukuro Ikusaba]].]]

** Also, once it's revealed that the infamous serial killer "Genocide Jack" is in fact a girl--Toko Fukawa's SplitPersonality--she notes that "Genocide Jill" is more accurate. Both "Jack" and "Jill" are used by the students to refer to her afterwards, but "Jill" becomes more common.

** Played with in the final execution. Junko, after failing to convince the survivors to vote for Makoto and stay in Hope's Peak Academy, decides to execute herself so that she can feel the "despair of death"... except that her brain is so warped that despair causes her what can be observed as absolute joy and glee, and faces the execution with a constant maniacal grin on her face, which only vanishes moments before her end.
* FailedExecutionNoSentence: Averted in Makoto's case. After he survives his execution, Monokuma announces that he plans on killing Makoto again. Kyoko saves Makoto by convincing Monokuma that this would amount to breaking his own rules and convincing him to let them redo the trial.
* FairPlayWhodunnit: ''Usually''. In most cases, Makoto can gather enough information before the trial starts to expose the culprit. However, a few cases have the murder scenes tampered with, usually by people with no involvement as victim or culprit, unfairly screwing everything up and having the player re-think the scenario. One case doesn't even get properly solved until the chapter after! Rule 10 of Knox's Decalogue (No identical twins or duplicates) is also broken, though the fact that they aren't ''totally'' identical is an important point.