Everyone says that the mikan case is BS and in some cases that it's the worst case of the entire series, however there is another case which you could say that is as bad as mikan's case and that's korekiyo's case from the third danganronpa game.

What i have noticed after analizing both cases i have thought that even though it's right that mikan's case is the worst case of danganronpa, it has one thing that is better than korekiyo's case and that's the trigger of the blackened's actions: in korekiyo's case he kills 2 people, angie which he does due to her appearing while he was preparing the seesaw effect and it wasn't planned originally by korekiyo who only intended to kill his second victim (tenko) with the seesaw effect, yet due to the sudden appearance of angie he decided to kill her so he could use the seesaw effect with tenko, so basically korekiyo killed 2 people but one of them happened because of the first victim's bad luck while the other was planned

Then we got mikan who also killed two people but this deaths were planned unlike korekiyo's even though korekiyo did his kills in a smarter way than mikan's

Finally we got the reason of why mikan and korekiyo killed 2 people and here is where i say that mikan has a better reason than korekiyo to kill, as you all know korekiyo wants to kill people so those killed become friends to her dead "sister" which is a very stupid reason to kill people since his "sister" is a personality of korekiyo himself, also what's even worse is the explanation of why did he kill tenko after killing angie because he says that it would be bad to not use the seesaw effect to kill someone, basically he indirectly said that he killed tenko because he could.

Now we go with mikan's reason to become a killer which is simple yet it makes sense unlike korekiyo's reason to kill: as you all know in chapter 3 of the second game monokuma informs of the despair disease which basically makes the people infected become the complete opposite of themselves, this gives a reason for mikan to kill since during the first two chapters she doesn't have the "killing vibe" that the other blackened had (specially the second) and wasn't very intelligent, however since the virus makes you act unlike yourself, one can deduce that mikan became the complete of herself a very intelligent girl who didn't care about killing people, this basically makes mikan pass from being a character which makes you think "she won't kill anybody" to one that makes you say "she'll kill someone" during the chapter.

In resume mikan turning into the complete opposite of herself due to the despair disease which makes mikan kill 2 people easily beats korekiyo's fucked up reasons to kill two people (bringing friends to her dead "sister" who is an personality of korekiyo and because he could in the case of the second kill)

So even though mikan's case is the worst of the entire danganronpa games saga, it has a better trigger for the killings of the blackened than the triggers of korekiyo's kills