Tear Jerker / Trollhunters: Rise of the Titans

• Jim clearly has PTSD from the year or so that he spent as a Trollhunter, including the few months turned into a troll. He keeps saying that he needs to be the Trollhunter to protect his friends and sees his realistic injuries — bruised ribs from being knocked off a train — as weakness. His human friends and family have a different response: they tell him You Can Barely Stand and encourage him that he doesn't have to be the hero for them.
• Nomura's death; a mind-controlled Nari grabs her limbs, holds her in the sunlight to petrify her, then shatters her, all while Douxie and AAARRRGGHH!!! can only watch helplessly.
• Archie and Charlemagne getting stuck in the Chinese Trollmarket. While they intend to claim the area as their own kingdom, the whole area was collapsing as its material lynchpin (the bridge) broke up the Titan's might and weight. Archie begs Claire to let Douxie know he said goodbye.
• Strickler making a sacrifice to kill the Ice Titan by blowing himself up all while telling Jim how proud he is of him. Jim was planning to blow up the Titan, but the Titan knocking him down worsened his rib injuries, and Strickler froze his wings breaking Jim's fall. Strickler then gives a speech, saying that once he tried to kill his adoptive stepson, and says that it was the best failure that a troll could have, reassuring him with a smile. And it is ultimately pointless, as the Titan reforms quickly afterward. And this is after we learned that he and Barbara got engaged.
• Barbara and Jim console each other about Strickler's death, with Barbara telling Jim that it wasn't his fault. She affirms that their desire to help others runs in the family, and they will support each other every step of the way.
• Nari's My God, What Have I Done? when Douxie snaps her out of her brainwashing. She whimpers, not remembering that she killed Nomura but sees that the Titan is awakened, and senses something terrible has happened. The Trollhunters forgive her, with Douxie giving her a Cooldown Hug.
• Nari dying in a Mutual Kill with Skrael, even worse as her death leaves the heroes with even fewer options to fight against Bellroc.
• Toby dies after helping Jim kill Bellroc since the collapsing Fire Titan crushed the truck Toby was in. And this wasn't a death that could be reversed with magic or alien technology. If Jim hadn't gone back in time in the end, Toby would actually stay dead.
• Jim decides to go back in time, to save Toby and everyone else who died stopping the Titans. To do so, he must leave behind all the friends he made and undo all their experiences together, which he accepts because he believes destiny will bring them together again. What makes it bittersweet is that everyone else, even Claire, agrees. But even so, Claire begs Jim to ensure they both still fall in love.

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