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Tear Jerker: Mega Man Defender Of The Human Race
Mega Man: Defender of the Human Race has so many sad moments the author termed them "Defender moments."
The first major one is in episode 3, with the death of Doc the Metool.
Dr. Cossack's near-heroic sacrifice in episode 6.
Episode 8 has Mega's reaction to Roll being trapped in the tower. He screams her name and pounds frantically on the walls, to no avail.
ProtoMan being demoted in the episode 9 epilogue, as well as explicitly ordered to never leave the fortress without Wily's say-so.
Episode 10 has Mega lamenting that after the war his friendships might fade. Then later he discovers Kalinka's cutting scar, showing how badly she was hurting after her mom died.
Everything post home invasion in episode 10, especially Roll and Peekaboo, and Kalinka's second kidnapping.
The climax of episode 10, with Ballade's death and an innocent girl's paralyzation.
Everything in the epilogue of episode 10. Tiesel finds out the hard way that he can't back out of his deal with the Conduit, Mr. Black is tormented over memories of his wife, Janet is paralyzed and hurt to such a degree that she can't be operated on, Mega Man is horribly traumatized over this and cries with Kalinka and his family over it, and ProtoMan is cold-bloodedly tortured by Wily even after begging him to stop.
The first chapter of episode 11 continues the sad train, especially the last scene, featuring ProtoMan.
The second chapter of episode 11 has Wily rigging a conversation between Mega Man and ProtoMan to hit them where it hurts, and tear apart their shaky familial bond. What makes it worse is when Proto deviates from Wily's script and says how he really does feel about Mega, and his resentment over getting no respect and love from anyone. It ends with Mega crying.
Some choice quotes:
ProtoMan: ...Every time I see you, it's just a reminder of everything I'll never be... I hate you for it. Things would have been a lot better if... if you were dead.
Mega Man: When you felt bad for blasting that ion bomb in Times Square, I could tell you wanted a family to love you! You're just going to throw that away now?
ProtoMan: Maybe I do want a family, but no family wants me!
Mega Man: You might hate me and my family for who are and what we stand for... but, no matter what we went through, I never forgot that you were my brother! I always loved you!
The third chapter of episode 11 has Mega Man coming home from the above scene and telling his family about it.
It also has both Proto and Mega reflecting on the park conversation from episode 5, Dr. Light and Roll trying to help Mega Man through his depression, and Mr. Black remembering good times with his wife before she died.
Mega Man: I just want everything to be normal again... I don't want to fight anymore.
The fifth chapter of episode 11 has Roll's life flashing before her eyes as she's buried in a collapsed building. While she survives, how she does can also bring tears, as Mega Man thanks Bass for saving her... in front of ProtoMan, who'd been forced to stop her from being saved.
The sixth episode 11 chapter has Mega seeing the full video of ProtoMan's activation, Roll trying and failing to get Bass to change his ways, and Wily invoking and weaponizing a heartwarming moment between himself and Bass to hurt ProtoMan.
Episode 11, chapter 7, has ProtoMan's continued downward spiral and the slaughter of the entire army sent to fight with Mega Man.
Episode 11 chapter 8 has Rock deciding to quit being Mega Man, shattered over the trauma he and others have suffered.
It also has ProtoMan finally regaining his courage and confidence back after they were literally taken from him. And Wily burning the photograph of Proto and Mega together.
Episode 11, chapter 9, has Dr. Light giving in to despair. Roll desperately tries to convince Mega Man to rethink his decision to retire, but despite pressure he's unsure...so she slaps him and says if he lets Wily take over she'll never forgive him. Mega Man then reviews the footage and memories of all of Wily's prior attacks so he has a clearer mindset of what he's fighting against... and the humans he's fighting for.
Mr. Black's full memory of Tonya's death.
Episode 11, chapter 11 has the big moment. ProtoMan is forced to kill Mega Man via the Mad Grinder, and seems helpless to do so due to Wily's override command. But memories of his brother, Nomad, and Mega Man never doubting that he loves ProtoMan convince him to turn his back on Wily, saving his brother's life and the world.
The entirety of Episode 11, chapter 12. The whole chapter deals with the fallout from the previous one and Dr. Light, Roll, Rush, and ProtoMan doing their best to save a critically injured Mega Man. Some choice scenes:
Dr. Light being forced to sop up Mega's oil/blood with his lab coat.
Roll tearfully asking ProtoMan how he could hate her brother.
ProtoMan allowing his own internal regulator to be removed and swapped to help Mega...and that doesn't work until two hours later.
Proto taking off his visor to look on Mega Man with his own eyes. Dr. Light notices his face hasn't changed a bit since he left.
ProtoMan: ... I don't want you to die... I don't hate you, I never did... I love you, little brother. Dr Light: There has to be one more miracle left in this old body of mine, Rock. And I intend to find it in time to save you.
Everyone from the Bonnes, the President, Governor Deacon, the New York police, and Kalinka Cossack reacting to the news of Mega's condition.
The symbolism of ProtoMan literally giving Mega Man his heart.
The chapter ends with happy tears, as Mega Man wakes up, remembers his family, and gives ProtoMan a real, brotherly hug.
After everything he's done, Dr. Wily gets one of these moments in the episode 11 epilogue. Genuinely devastated over ProtoMan leaving, Wily considers why it happened... and realizes that it's too late to fix anything, it's his own fault, and by hurting ProtoMan he was no better than his own abusive father. He even contemplates giving up the war at one point. Even though his rage takes over soon after, it was a humanizing, surprising moment for a character many readers had come to see as a monster.
In the interlude to Episode 12, part 1, Wily is still down over the events of the previous chapters, which makes Bass declare him weak.
Also, 68 percent of New York distrusts ProtoMan. Both Mega and Proto see this news on TV.
The interlude to episode 12, part 2, has a lot of sad or sobering moments involving ProtoMan, particularly how everyone cheering for the New Year stops when he steps forward.
Episode 12, chapter 2 has Miss T destroying Tonya's wedding dress.
The climax of episode 12 has Mega Man calling the ambulance to help a possibly fatally-wounded Mr. Black even after the latter betrayed him.
Mega Man: I promised to defend the human race...even him.