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16. after killing the character, have others think the character had betrayed them so they’d always hate them and remember them as traitors and never say nice things about them… Give your readers no chance to have group-therapy with other characters by making them the only ones who know the truth.
17. right before their death, show a side of them nobody has seen. (someone who is always tough and brave being genuinely scared of dying alone; someone who is always laughing being in tears before dying, etc.)
18. make them the only person who knows a big important secret that would help other characters in the story.
19. have them being lied to before dying. (thinking they’ve been betrayed; thinking they weren’t loved; thinking they’ve lost their loved ones, etc)
20. make the character very enthusiastic/passionate about a certain goal, constantly put stress on their goal, have them die unexpectedly before they can reach their goal.
and the best one…
21. have another beloved character kill them–better be a close friend to your character, one that absolutely nobody suspects, one that everyone can’t help but love, one who is always enthusiastic about things and encourages your character. THEN
reveal the truth only later when it’s too late and the a-hole character has already escaped.
have a cowardly character know the truth and never tell anyone else
have another character find out the truth and have them die before revealing it to others.
have the said character ^ not actually die, but go through something so they’d forget the friend of the deceased character is actually an asshole.
This way only your readers will know the truth, thus the frustration would be… most enjoyable for you.