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Tear Jerker: Kamen Rider Gaim
At this rate, the entire show can be considered one, as things get increasingly depressing with every episode. Especially upon rewatch. Get ready for the waterworks, because you're in for one of the most emotionally draining experiences in your entire life. We'll do our best to list the more important parts.
Kouta's Heroic BSOD in episode 4, after Kamen Rider Zangetsu nearly kills him in the forest.
Kaito's reasons for wanting to be strong. His father once had a company, but it was bought out by the Yggdrasil company. Kinda sad if you think about it.
Imagine being in Mai's position when a true friend/crush flat out leaves you for a long period of time. Her frustration with Kouta is rather understandable because of that.
The look on Micchy's face when he sees Zangetsu and recognizes the belt as the same one his brother was hiding in an earlier episode. It is almost heartbreaking to see Micchy's face and thoughts as it dawns on him just how little he really knows about his older brother. Not to mention the realization that it was Takatora who attacked Kouta in Helheim Forest. It's so bad that Micchy kinda freezes up, and Kouta has to pull him away.
#12: The aftermath of Ryoji losing to Kaito. His belt already destroyed, he also loses his Lock Seed and stage to Team Baron. His teammates desert him, and Hideyasu (who refused to help him out) coldly declares he’ll find himself “a new doormat”. Poor guy…
The people of Zawame City turning against the Beat Riders, due to the some sort of virus leaking off of the Inves, making people sick. It's really sad to see the people turn against the ones who have been bringing them joy for likely years.
Crosses a bit into Nightmare Fuel, but the fact they cheer for Bravo beating up a kid and possibly seriously injuring another.
#14: Kouta's reaction to Hase's transformation into an Inves. From trying to reason with him and getting smacked aside, to faltering in delivering the final blow when he engaged him while he was terrorizing innocent civilians. The expression on his face when Sid executes Hase after he continually pleads for him not to really conveyed the sheer tragedy of the situation.
The first Inves from the first episode, turned out to be Yuya. Meaning... Kouta unknowingly killed his missing friend.
To properly illustrate the above tearjerker, put this into perspective: For the most part, Kamen Rider, more importantly the Heisei Riders, focus on monsters using human guises. We're usually either introduced to the monster before their human identity or introduced to their human identity but have it revealed that they have a monster form all along or become one in the span of fifteen minutes from their debut. Here, we are introduced to Hase and he is no monster, whatsoever. In the time it takes from his debut to his death, we saw more and more of him. The tragedy comes with him, a long-term character who was part of the secondary cast, becoming the monster, not just the fact that he died. Very few Kamen Rider shows pull off something like what Gaim did.
#15: Micchy stopped Kouta from finding out about Yuya's fate, not wanting his friend to fall into despair about the mess he kinda caused.
While mitigated by the fact that they ditched him in the first place, seeing the Raid Wild Riders wondering about the whereabouts of the (unbeknownst to them) deceased Hase is really tragic and dramatic.
#16: Seeing Mai on the verge of tears. What makes this so sad is that it's RARE to see Mai in this sort of position of helplessness and sadness.
Whatever it was that Takatora showed Micchy must be one. The sight of it brought Micchy to his knees and utterly broke him enough for him to change sides. Hell, even seeing how Micchy reacts to the sight is definitely one. He is traumatized.
#18: Things haven't gotten better for our heroes. After Kouta beat some Inves, he went over to make sure the people were okay, when they fled from him like he was one of them.
#19: You can just feel the tears about to come from Mai's face when Kouta tells her, he won't stay with Team Gaim.
#20: All of the Inves were human/animals at one point. All of them.
Kouta's face as he looked at the ruins of the city within Helheim. Never had we seen his resolve broke so fast and hard, which only gets worse when Takatora tells Kouta that all of the Inves were once humans. It was Ryoji all over again...
The information we're fed makes Micchy's actions concerning trying to make Kouta and Mai happy the past few episodes, as well as him saying that he'll betray anyone to achieve joy, all the more poignant. Wouldn't it be what you would do if you were one of the select few who were told the world will end in ten years?
While it's been very obvious before, this is the episode where it becomes clear that Takatora is a pawn to the other Energy Riders, who are all Ax Crazy Social Darwinists. It's sad, seeing Takatora care for them so much and actually trying to do the right thing while his "friends" use him so Helheim can kill the weak.
#21: You could see the look on Micchy's face when he finds out that Kouta's flame of hatred towards Yggdrasil has been relit and the utter heartbreak he has. It's only inevitable that he will have to reveal his working with Yggdrasil sooner or later.
#22: The dreaded moment fans were waiting for has finally appeared and Takatora personally shows Kouta the video file of Yuuya's last moments, including his destruction by Kouta's unintentional hands. One questions if Urobutcher is trying to turn Kouta into an Expy of Shinji Ikari or Madoka Kaname. Though other fans are worried that Kouta, considering that the next episode has him don Kachidoki Arms and indicating a He's Back moment, will adopt a mind of steel.
Micchy leading Team Gaim to a safety bunker in case an Inves manages to emerge from the public crack just has a powerful impact of sadness.
Although the Tokkyuger crossover was generally a happy go lucky episode, there was a sad part that the situation was so bad that Kouta was willing to never see Mai again so she would be safe
#24: Kouta and Mitchy fighting. It really shows how fractured their friendship has become...
For all his Jerk Ass-ness, Jonouchi's Character Development in this episode makes him quite sympathetic; he knows he's a fake, he's been betrayed (sort of) by his friends and because of this, envies Oren and Kouta. Hell, he even regrets leaving Hase. Even if his hard work and mocking ends up as CMO Fs, this is still a Hidden Depth for the guy.
The look on Kouta's face when Jonouchi wonders how Hase is doing just tells it all. The fact that he's hesitant to tell him only makes it more saddening. The only thing lifting the mood is the light-hearted music.
Kouta's face when Mai demands answers from him about Yuya. His look of heartbreak when he knew what he's going to reveal to her, and worst part is, he knows Mitchy is not going to like it, but damn it all if he can't keep it all a secret.
#26: Micchy tried so hard to avoid telling Mai that Yuya had died, and after managing to prevent the Beat Riders from breaking the Masquerade chides Kouta for breaking their promise to keep Yuya's death a secret. But the worst part hits when Mai slaps Micchy for being uncaring of Kouta's motivations, and anyone could see with that slap, any remaining shred of Micchy's Nice Guy persona is gone as he completes his Face-Heel Turn.
The scene between Kouta and Mai at the beginning of the episode.
#27: Micchy shot Kouta in the back in the last episode right before he went Kachidoki Arms, knocking him out, and was this close on killing Kouta. Already, this is showing how far apart the two Riders are, but if Kouta ever learns about this, Urobuchi knows how he'll react.
#28: Takatora being betrayed by the other Energy Riders (sans Baron). We knew it was coming, but to see a good man like Takatora went down was still hard to swallow. Especially since his last moment was him conversing with Micchy, who we knew is on Ryoma's side.
Kouta watch on Micchi as Zangetsu Shin VS Baron Energy. He still believed that the guy in the suit is Takatora, who just last episode formed an alliance with him. The look on his face as he tried to stop them is heartbreaking.
#29: Hearing Roshuo talk about the downfall of his world. Like Takatora, he'd believed he was making a better world...all he'd done was create a world were the strong hunted down the weak, then destroyed one another, leaving him with nothing but the ruins of his home and two Ax-Crazy psychopaths and the hordes of monsters that used to be his world's people for company.
#31: And it just gets worse from before as Takatora isn't the only one with a comparison. Kaito and Deemushu both think that the weak are prey for the strong, while both Micchi and Redyue are schemers who'd rather use others to get the power or the goals they want. The Tear Jerker in it all is that Kaito at least seems aware of this and still holds onto his own... moral compass of sorts. Currently the only difference between Micchi and Redyue is the fact that one jangles when he moves about.
#32: Deemushu is destroyed. While the psycho deserved it, one can only imagine how it must feel for Roshuo to have one of the few remaining members of his species die.
Also, Mitsuzane's look on his face when he sees Sid's hat. Considering how he allied with him in the previous episodes, Sid could have easily been the only friend/ally he had left. This also leads to the tearjerker that Mitsuzane fell so far from grace if he considered Sid to be a friend.
Kouta struggling to reach the Kiwami Lockseed in spite of Mai's protests and even though Sagara all but admits he's playing Kouta for his own ends. Despite the fact that Mai's begging him not to take that power, Kouta can't bring himself to abandon his friends. His sheer desperation is truly tearjerking.
#33: Micchi's laugh at the end and in the trailer. It's not a laugh of joy, or satisfaction. It's a laugh of a madman, a man who's gone too far for his own power, who sees his best friend as his worst enemy, and is willing to have humanity enslaved simply for his feelings towards one girl. And the worst part is he thinks he's in the right.
#35: Kouta finally finds out about Micchy's betrayal, and in a painful way. Seeing your best friend kicking, punching and attempting to kill you is truly heartbreaking.
Takatora hiding behind watching Micchy beating Kouta up, while learning that his own brother has stolen his identity as Zangetsu Shin. Remember how he had high hopes for his brother to save humanity, and finally acknowledged Micchy's friendship with Kouta before? Imagine how devastated he must feel when he sees how twisted his brother has become.
What makes all of this even worse is that the revelation of Micchy's Face-Heel Turn comes completely out of nowhere for both men. Micchy had done such a good job of keeping his villainous tendencies a secret that neither of them ever suspected that he was capable of acting so monstrously.
#36: Takatora losing to Mitsuzane. Despite the fact that he knew Mitsuzane was now a threat to humanity, he hesitated for a moment because deep inside he wanted to believe his little brother has not changed from the same person he was many years ago. Unfortunately for Takatora, Mitsuzane took this hesitation and smashed him into the water and knocked off his Sengoku Driver, leaving him to sink into the lake of Zawame City.
Golden Cup Movie: The destruction of the alternate world at Lapis' death, causing Hase and Sid to die once more, Micchy to return to his evil ways, and Kaito on the verge of possible death.
Not helped by the fact when Kota returned to his normal world, he saw the remains of Lapis, his weapon as a Rider and his bracelet.
#39: The Rider Alliance being forced to leave behind Oren and Hideyasu to face a large horde of Inves made up of both the Elementary and Berserker variants. Granted, both of them told the others to go on without them, but still...
Kota's denial to Ryoma saying that they're dead makes it more unfortunate...
#40: Kouta's situation in ep 40. Force into a dream world by Redyue, he became the Byakko Invess. The results? Yuuya as Gaim relentlessly hunted him down, Zack/Knuckle and Yoko/Malika - two of his new allies - are now trying to murder him as well, the people he fought to protect now run away from him at first sight. He came very close to joining the Invess but chose otherwise at the end.
Unfortunately, the next scene after that shows that Kouta IS becoming an Overlord: When he dehenshinned, multiple Helhelm vines spread out with him at it center. No matter what happen, Kouta Kazuraba can never go back to his life as a human again.
The fact that Kouta, who is unwilling to give up on the world or its people to Helheim, is okay with sacrificing his humanity if it means it would stop the Helheim invasion, even if in the end no one else was on his side or believed in his cause.
Mai's situation: Her city and her world is almost gone, one of her friends turned evil and put her next to the man responsible for the world's state, and now she just found out that her friend/crush will have to choose between 2 sadistic choices as a price for his power - a choice that she already knows the answer to.
#41: The last shot of Roshuo lying dead on the ground when Sagara and the spirit of the queen stop by. After seeing all he went through just to revive his queen lead to his death at the hands of one of the last of his kind, the shot of the queen's coffin shows that it wasn't going to work anyway.
#42: Micchy gets an oddly tragic moment this episode when he breaks down crying over Mai's unconscious body while begging her to smile like she used to because he's forgotten what her smile looks like. It's tragic seeing him realize that everything he's done has been for nothing. He doesn't even scream at his hallucination of Takatora this time, he just quietly asks it to shut up.
The fact that Micchy no longer values his own life is a bit tragic in itself. What was once a cheerful and friendly person is now a husk who doesn't care if he lives or dies. Even worse is the reason he's using the Hell Fruit Lockseed in the first place: Ryoma tricked him into thinking Kouta wants Mai to become the "Woman of the Beginning" and lose her humanity. He's literally throwing his life away for NOTHING.