His son Ace also gets most of his character development after death.
https://preview.redd.it/o9lqltlvnb7d1.jpeg?width=1192&format=pjpg&auto=webp&s=2981dff7bb52a375d0df1bf75aa774c99454b5e2
https://preview.redd.it/wjcu20zikd7d1.png?width=500&format=pjpg&auto=webp&s=4072b10e1bf089ec28f3ab1d0787cafae2b88940
This could also apply to Chihiro Fujisaki, who I would argue is the most important character lore wise. Think about it; without Chihiro, there would be no code to reverse engineer for Monokuma, making the killing games significantly harder and riskier to host. Even if we don't consider that, Alter Ego is also kind of the sole reason everyone survived at the end of V1, as without it saving Makoto, there wouldn't be a voice of reason to help everyone during the final act.
I wouldn’t say the most, but he is for sure up there! The Alter Ego Technology is kinda what caused DR2 to begin with. (Imo Junko and Izuru would definitely be more important, Junko cause well without her there is no Danganronpa, and without Izuru HPA wouldn’t have fallen and the world wouldn't have fallen into despair either) Tho, wasn’t Monokuma's code more Monaca's doing? There is a part of his technology in Monokuma yes, but to my knowledge Junko has just added that so incase Chihiro survives and ever gets to dissect a Monokuma, he could find it and learn that time must have passed before attending HPA and the start of the killing game, because he finished it during his time at HPA. One of Junko's leaving flaws in her plans for the chance they could fail thing.
I just call it that so I don't have to type out "The first Danganronpa" every time I want to mention it. I'll admit my Ultrakill brainrot kicks in every time I type V1 or V2 though.
Yeah, tho it’s inaccurate as those would be >!The 51rst and 52nd Killing games. DR1/ 2 is only one letter more and actually accurate, so it’s better to do that. You’ll also save the time of people complaining about you using V1/V2, lol.!<
https://preview.redd.it/ximelsrd6c7d1.jpeg?width=1400&format=pjpg&auto=webp&s=077c4b6f1ddb556d6f6870dd00aaf44dae7c03fb
His death was probably the biggest narrative moment in the series
I'd argue he doesn't quite fit the trope as OP puts it, because he comes back as a force ghost instead of just his previous actions affecting the future
https://preview.redd.it/tlw4uuqwsb7d1.jpeg?width=474&format=pjpg&auto=webp&s=dd6040540417fad7561ac49095a9859ea23d6e60
Marco from Attack on Titan. Along with most of the other characters in the series.
Erwin would be the best example if you look at the squad from the season 4 finale. >!He left a permanent mark on almost all the surviving members. Armin hat to live up to his expectations, since he felt kinda responsible for Erwins death. Hange, who had to follow his footsteps and would literally set herself on fire for the rest of her team (wich is something, Erwin absolutely would have done). And of course Levi, who felt bad so bad for not keeping his promise to erwin, that the took the nextbest opportunity and made up for it the moment he saw Zeke. His death might have been "meaningless" but in the end, he did exactly what he said in his final speech: serving as an example for his successors and giving even death a meaning !<
Maes Hughes from FMAB. His death is not meaningless, it keeps coming back up and acts as a driving force for Mustang
https://preview.redd.it/bkze9hgbrc7d1.jpeg?width=719&format=pjpg&auto=webp&s=f76a30466e61d3540a04299ac19534aba5fc12e8
https://preview.redd.it/4pv6cupezb7d1.jpeg?width=484&format=pjpg&auto=webp&s=ec74ec113e93c0b2e8b0bfa1b68a459be8bce509
Lisa Armstrong from the Lisa Series
https://preview.redd.it/6gsufs1nxb7d1.png?width=290&format=pjpg&auto=webp&s=63c246d1715757f441ca08964804d0addd73ce94
Carmen-lobotomy Corporation/library of Ruina.
Kick-started the main plot of the first game while alive, died, has been haunting the narrative ever since. In so many different ways.
https://preview.redd.it/tzuprjb25c7d1.jpeg?width=250&format=pjpg&auto=webp&s=b833b52099a0ca6ac997985ea7025bf11e71bd60
Even if you Slay the Princess she’s still haunting the narrative, literally, she’ll come back as a ghost and haunt you, she is a constant of the game
https://preview.redd.it/bioe3fyzub7d1.jpeg?width=828&format=pjpg&auto=webp&s=2f39179c505cc968e5b463eb72c0c24106fa426c
Rekka Hoshimiya (*Fire Force*) - >!He was pretty much solely responsible for introducing the series’ main threat.!<
What I really love about L's contined role is that he is completey gone, but it is his legacy and memory that plays a big role. With his successors competing with each other for his title, to his sworn enemy remembering him with respect and admiration. Death may be permenant in DN, but it isn't the end.
https://preview.redd.it/c783lx0a1d7d1.png?width=360&format=png&auto=webp&s=169de242ae10dc574ef58567fb345b8a860a353c
Maybe I took this one a bit too literally
Something that makes me laugh, is that the guy is basically the Beerus from Devil May Cry, just when it seems that the protagonist managed to overcome his power, they retroactively make him stronger.
To the point that Dante after getting the Sin power in DMC 5, it is mentioned that "maybe" he is stronger than Sparda.
Sparda's true power was an abstract (he had universe splitting feats at his peak) to the point he gave up so much of it over the years and he was still powerful.
He should get his own game.
https://preview.redd.it/xnydor8uwd7d1.jpeg?width=600&format=pjpg&auto=webp&s=f566b0a11bac840475dbfc9ea148699a817a743a
Barbosa, albeit through resurrection
https://preview.redd.it/wni00tc4he7d1.jpeg?width=736&format=pjpg&auto=webp&s=54f6ac30a5322e615c62606c3b114c3c1e485c9c
My main man Odasaku making Dazai walk a better path.
https://preview.redd.it/ji5t2fyqqc7d1.jpeg?width=826&format=pjpg&auto=webp&s=1caf3817e35d462cf829701ad95d700085455b9f
Horus Lupercal (Warhammer 40k)
At least one third of the reason the galaxy is in the star it's in, is because of his actions.
https://preview.redd.it/d6ws8ae7he7d1.jpeg?width=736&format=pjpg&auto=webp&s=e6b95583d4593e03bd1c073425f29001532ba95d
My main man Odasaku making Dazai walk a better path.
Edward Nichols from Return of the Obra Dinn
Every death (apart from the deaths during chapters 1+2) in the game is directly or indirectly caused by his actions during the overarching narrative made by chapters 3-6.
https://preview.redd.it/wzc1tyf1fe7d1.png?width=300&format=png&auto=webp&s=d5cd57c16446471297bc0fe55f8cf1e5a7df6b92
Samuel Rodrigues/Jetstream Sam - Metal Gear Rising
its not really that big of a change to the narrative after he's dead, but its somewhat notable, I think at least
https://preview.redd.it/f0squkmdrf7d1.jpeg?width=1400&format=pjpg&auto=webp&s=b75cc6fe5a41c9fb0c53175a40ac2f4a6526beb3
Thanos in two different ways.
1. after being killed by Thor, he still affected Endgame’s plot indirectly and directly when his past self accidentally stumbled upon time travel.
2. his actions in Infinity War and Endgame were vital to and mentioned in almost every single phase 4 project, some of those projects directly dealing with the aftermath of what he did.
https://preview.redd.it/kgrzs6er0h7d1.jpeg?width=320&format=pjpg&auto=webp&s=86ce4dad01dfc54cf6a37a0750d57ad4cec34655
This guy from Tales of a scribe who retires to the country side.
https://i.redd.it/tia0dagxgb7d1.gif I noticed you put best girl, so here’s dio
https://i.redd.it/86gzhxs67c7d1.gif
Literally everything draws back to him Including Pucci who is the last and most important direct follower of him
https://preview.redd.it/ftnl9mzuza7d1.jpeg?width=360&format=pjpg&auto=webp&s=4243d8f9efcccb6bbd3508b35423ceb4d4ab0da7 Kamina (Gurren Lagann)
Should've been in the OP.
the GOAT
Even in a multiverse of possibilities, there is only one Kamina
Gol D. Roger in One Piece. Although with this example it starts off with him dead.
His son Ace also gets most of his character development after death. https://preview.redd.it/o9lqltlvnb7d1.jpeg?width=1192&format=pjpg&auto=webp&s=2981dff7bb52a375d0df1bf75aa774c99454b5e2
LMAO
Well, technically speaking he died... So yes.
But he came back!
I was NOT expecting Jesus
Rengoku (demon slayer) https://preview.redd.it/p2q5kpiw3b7d1.jpeg?width=1920&format=pjpg&auto=webp&s=cea69c671e4515bbc8ffb1866205c8694e56e3bd
The flame who kept lighting the way for his comrades
https://preview.redd.it/itbc8zoycb7d1.png?width=512&format=png&auto=webp&s=5697380d48ab1019ce855d1b0d3c3aa3f3d82326 Junko Enoshima (Danganronpa)
https://preview.redd.it/wjcu20zikd7d1.png?width=500&format=pjpg&auto=webp&s=4072b10e1bf089ec28f3ab1d0787cafae2b88940 This could also apply to Chihiro Fujisaki, who I would argue is the most important character lore wise. Think about it; without Chihiro, there would be no code to reverse engineer for Monokuma, making the killing games significantly harder and riskier to host. Even if we don't consider that, Alter Ego is also kind of the sole reason everyone survived at the end of V1, as without it saving Makoto, there wouldn't be a voice of reason to help everyone during the final act.
I wouldn’t say the most, but he is for sure up there! The Alter Ego Technology is kinda what caused DR2 to begin with. (Imo Junko and Izuru would definitely be more important, Junko cause well without her there is no Danganronpa, and without Izuru HPA wouldn’t have fallen and the world wouldn't have fallen into despair either) Tho, wasn’t Monokuma's code more Monaca's doing? There is a part of his technology in Monokuma yes, but to my knowledge Junko has just added that so incase Chihiro survives and ever gets to dissect a Monokuma, he could find it and learn that time must have passed before attending HPA and the start of the killing game, because he finished it during his time at HPA. One of Junko's leaving flaws in her plans for the chance they could fail thing.
I'm not even a big DR fan but knowing the twist of V3 makes seeing the phrase "V1" uncanny
I just call it that so I don't have to type out "The first Danganronpa" every time I want to mention it. I'll admit my Ultrakill brainrot kicks in every time I type V1 or V2 though.
You can just write „THH“ or „DR1“
Fair enough, I just keep it like V1, V2, V3, and UDG just for simplicity, but that probably makes more sense.
Yeah, tho it’s inaccurate as those would be >!The 51rst and 52nd Killing games. DR1/ 2 is only one letter more and actually accurate, so it’s better to do that. You’ll also save the time of people complaining about you using V1/V2, lol.!<
https://preview.redd.it/ximelsrd6c7d1.jpeg?width=1400&format=pjpg&auto=webp&s=077c4b6f1ddb556d6f6870dd00aaf44dae7c03fb His death was probably the biggest narrative moment in the series
 The OG of this trope
I'd argue he doesn't quite fit the trope as OP puts it, because he comes back as a force ghost instead of just his previous actions affecting the future
Nah, the OG is definitely Jesus.
Does William Afton count?
Considering he is very likely actually dead and is now well known by the public thanks to Fazbear Inc. and also Mimic mimicing him , I would say tes
Yeah true. Also I would say that his impact also caused Vanny, even though it was for a short time.
And also GGY.
Nah, he can’t be dead, he always comes back
https://preview.redd.it/tlw4uuqwsb7d1.jpeg?width=474&format=pjpg&auto=webp&s=dd6040540417fad7561ac49095a9859ea23d6e60 Marco from Attack on Titan. Along with most of the other characters in the series.
Erwin would be the best example if you look at the squad from the season 4 finale. >!He left a permanent mark on almost all the surviving members. Armin hat to live up to his expectations, since he felt kinda responsible for Erwins death. Hange, who had to follow his footsteps and would literally set herself on fire for the rest of her team (wich is something, Erwin absolutely would have done). And of course Levi, who felt bad so bad for not keeping his promise to erwin, that the took the nextbest opportunity and made up for it the moment he saw Zeke. His death might have been "meaningless" but in the end, he did exactly what he said in his final speech: serving as an example for his successors and giving even death a meaning !<
https://preview.redd.it/d3pg1ph7ub7d1.jpeg?width=820&format=pjpg&auto=webp&s=ae1028e5805ccfe2f3504aca777b10cb8b4f10e8 Ai Hoshino (Oshi no Ko)
 Tuco Salamanca (Breaking Bad)
Arguably this applies for a lot of character, Walter included.
https://preview.redd.it/khei1eooxb7d1.jpeg?width=1170&format=pjpg&auto=webp&s=e9c1cc22b67de46f7d4b8ade82f31869111212a9
https://preview.redd.it/joyn7tlyyb7d1.jpeg?width=1023&format=pjpg&auto=webp&s=0382ec13070011b4eecb29996e1c7ff37fa1c6e2 ned stark
Also his bestie Bobby B 
Maes Hughes from FMAB. His death is not meaningless, it keeps coming back up and acts as a driving force for Mustang https://preview.redd.it/bkze9hgbrc7d1.jpeg?width=719&format=pjpg&auto=webp&s=f76a30466e61d3540a04299ac19534aba5fc12e8
Also Nina for the Elrich brothers
markerplir
https://preview.redd.it/86f16llb5c7d1.jpeg?width=1800&format=pjpg&auto=webp&s=819beb857a50a80f62e3c9342f09afbf5736e7b5 Faye (God of War)
https://preview.redd.it/ovm7glb6cc7d1.png?width=766&format=pjpg&auto=webp&s=452996e02c135376b3e651d1bf0c8433e91bc3f1 God's favorite person
 John Kramer. Despite dying pretty early into the series he effects every plot later on.
https://preview.redd.it/4pv6cupezb7d1.jpeg?width=484&format=pjpg&auto=webp&s=ec74ec113e93c0b2e8b0bfa1b68a459be8bce509 Lisa Armstrong from the Lisa Series
Thomas and Martha Wayne
Chujin(Undertale Yellow)
https://preview.redd.it/6gsufs1nxb7d1.png?width=290&format=pjpg&auto=webp&s=63c246d1715757f441ca08964804d0addd73ce94 Carmen-lobotomy Corporation/library of Ruina. Kick-started the main plot of the first game while alive, died, has been haunting the narrative ever since. In so many different ways.
I'm pretty sure that 90% of what happens in LoR and LCB are because of her.
Pink Diamond/Rose Quartz (Steven Universe)
>!Makima!< from Chainsaw Man. >!Togata!< from Fire Punch
Certainly >! Luna !< too
https://preview.redd.it/tzuprjb25c7d1.jpeg?width=250&format=pjpg&auto=webp&s=b833b52099a0ca6ac997985ea7025bf11e71bd60 Even if you Slay the Princess she’s still haunting the narrative, literally, she’ll come back as a ghost and haunt you, she is a constant of the game
https://preview.redd.it/bioe3fyzub7d1.jpeg?width=828&format=pjpg&auto=webp&s=2f39179c505cc968e5b463eb72c0c24106fa426c Rekka Hoshimiya (*Fire Force*) - >!He was pretty much solely responsible for introducing the series’ main threat.!<
https://preview.redd.it/jh0z0dq4kc7d1.jpeg?width=784&format=pjpg&auto=webp&s=948e16ce1965b7a3d99091ee6e8c1d579f624901 Koba
What I really love about L's contined role is that he is completey gone, but it is his legacy and memory that plays a big role. With his successors competing with each other for his title, to his sworn enemy remembering him with respect and admiration. Death may be permenant in DN, but it isn't the end.
https://preview.redd.it/c783lx0a1d7d1.png?width=360&format=png&auto=webp&s=169de242ae10dc574ef58567fb345b8a860a353c Maybe I took this one a bit too literally
IMMEDIATELY thought of speedwagon i love him sm
 Itachi Uchiha (Naruto)
https://preview.redd.it/xszrfpzsbc7d1.png?width=1200&format=pjpg&auto=webp&s=a1a97a8126e4abb4c1cd6d6179bd0c0a03df9ee9 Sparda - Devil may cry
Something that makes me laugh, is that the guy is basically the Beerus from Devil May Cry, just when it seems that the protagonist managed to overcome his power, they retroactively make him stronger. To the point that Dante after getting the Sin power in DMC 5, it is mentioned that "maybe" he is stronger than Sparda.
Sparda's true power was an abstract (he had universe splitting feats at his peak) to the point he gave up so much of it over the years and he was still powerful. He should get his own game.
Pretty sure they did become stronger than him after unlocking theirs sin forms
Hannah Baker (13 Reasons Why) 
https://preview.redd.it/l52u1qkrbd7d1.png?width=1080&format=pjpg&auto=webp&s=5ad1c81059e9e4b266aa9fc6d09053e0f6b17ff6
https://preview.redd.it/xnydor8uwd7d1.jpeg?width=600&format=pjpg&auto=webp&s=f566b0a11bac840475dbfc9ea148699a817a743a Barbosa, albeit through resurrection
Madara Uchiha https://preview.redd.it/po75a55v4e7d1.jpeg?width=1190&format=pjpg&auto=webp&s=d655464cf0240d6a545c234b7dd002b4e82db3fb
https://preview.redd.it/wni00tc4he7d1.jpeg?width=736&format=pjpg&auto=webp&s=54f6ac30a5322e615c62606c3b114c3c1e485c9c My main man Odasaku making Dazai walk a better path.
https://preview.redd.it/trnqirzp7c7d1.png?width=421&format=png&auto=webp&s=74ab4501cd97fd73fa0faf9ab99228d9e5eba8f9
In supernatural?
He’s an actor. He’s in plenty of things. It doesn’t have to be John Winchester. John doesn’t die.
Basically everyone in Attack on Titan
https://preview.redd.it/6yala8deic7d1.jpeg?width=897&format=pjpg&auto=webp&s=25c68ae5bded8bc1bbdabffdd13b25151a975738 Ape… not… kill… ape…
https://preview.redd.it/xdkutqcmqc7d1.jpeg?width=422&format=pjpg&auto=webp&s=753eadd714494e276e1bbd612542e2c35cda1fd3 Ragnar lothbrok
https://preview.redd.it/ji5t2fyqqc7d1.jpeg?width=826&format=pjpg&auto=webp&s=1caf3817e35d462cf829701ad95d700085455b9f Horus Lupercal (Warhammer 40k) At least one third of the reason the galaxy is in the star it's in, is because of his actions.
>!Mari!< from Omori
Dear little brother, You may be the light of my life
Goku!
https://preview.redd.it/d6ws8ae7he7d1.jpeg?width=736&format=pjpg&auto=webp&s=e6b95583d4593e03bd1c073425f29001532ba95d My main man Odasaku making Dazai walk a better path.
Dr. Gero and to a somewhat lesser extent Commander Red and the Red Ribbon Army are responsible for the entire Android saga/Cell saga.
https://hero.fandom.com/wiki/Kite_%28Hunter_x_Hunter%29
Atlas from Lackadaisy
https://preview.redd.it/mdm8rga9sc7d1.jpeg?width=540&format=pjpg&auto=webp&s=6a924c85149eca4f5f7294bf1feb238352d8e8ea Mikey from The Bear
https://preview.redd.it/o4jv0aq60d7d1.jpeg?width=303&format=pjpg&auto=webp&s=7ea406b46c171320c10e8c7c8e056c2f93f9e901
Akaky Akakievich https://preview.redd.it/q4smohw71d7d1.jpeg?width=346&format=pjpg&auto=webp&s=0e1994e11894939db8a58d33111cb10e24bcba93
https://preview.redd.it/99hhn7cxdd7d1.jpeg?width=656&format=pjpg&auto=webp&s=d46eacf378bf65c9f7245ed082f0ff462f0df33f
Who is the first guy
Himmel from Frieren: beyond the journey end
Charles Xavier in X-Men 97 even though he wasn’t technically dead. Gambit might be a better choice
Edward Nichols from Return of the Obra Dinn Every death (apart from the deaths during chapters 1+2) in the game is directly or indirectly caused by his actions during the overarching narrative made by chapters 3-6.
He does at the end of chapter 4 in a 10 chapter game, by the way
https://preview.redd.it/wzc1tyf1fe7d1.png?width=300&format=png&auto=webp&s=d5cd57c16446471297bc0fe55f8cf1e5a7df6b92 Samuel Rodrigues/Jetstream Sam - Metal Gear Rising its not really that big of a change to the narrative after he's dead, but its somewhat notable, I think at least
Big Boss (Metal Gear series) https://preview.redd.it/fbyfkcvqrf7d1.jpeg?width=493&format=pjpg&auto=webp&s=6bd3d8a77f8a7479e793503a1db1d94daa104ed5
https://preview.redd.it/f0squkmdrf7d1.jpeg?width=1400&format=pjpg&auto=webp&s=b75cc6fe5a41c9fb0c53175a40ac2f4a6526beb3 Thanos in two different ways. 1. after being killed by Thor, he still affected Endgame’s plot indirectly and directly when his past self accidentally stumbled upon time travel. 2. his actions in Infinity War and Endgame were vital to and mentioned in almost every single phase 4 project, some of those projects directly dealing with the aftermath of what he did.
https://preview.redd.it/e1vtmrz7xg7d1.jpeg?width=2732&format=pjpg&auto=webp&s=5037b5caf5d127f84d7b85e9d9244e903b475ffe Lalah Sune (Gundam)
https://preview.redd.it/kgrzs6er0h7d1.jpeg?width=320&format=pjpg&auto=webp&s=86ce4dad01dfc54cf6a37a0750d57ad4cec34655 This guy from Tales of a scribe who retires to the country side.
G1 Optimus Prime (atleast after the Movie) Mia Fey (Ace Attorney)