Tear Jerker / The Dragon and the Butterfly

• The reason for the plot is that Hiccup's friendship with Toothless was discovered before Toothless showed him the nest. As such, Hiccup is disowned and Toothless is captured. Both know that the Vikings will probably kill them. Hiccup manages to save Toothless with the help of a Nadder, but she's captured during their escape. For their own safety, the boy and dragon have to leave the archipelago (where they've both spent their entire lives) for good.
• Not only is the abuse he faced during his time on Berk dialed up a bit, but Hiccup's trauma from said abuse is treated more realistically, with him having self-doubt issues and considering himself a burden to those who help him.
• It's still very hard for Bruno to be out among people. The first time he goes into town after emerging from Casita's walls, people start to crowd around him, glaring. It takes Hiccup snapping at them to make them back off.
• The state of Berk after Hiccup and Toothless leave. While the Vikings initially celebrate the disappearance of the two, the dragon raids get worse. Stoick goes through the Five Stages of Grief due to his son "betraying" his tribe, meaning that he can't lead his people as he normally would, while Gobber refuses to work due to his anger at the Vikings for driving Hiccup away (as well as grieving him, not knowing if he's even alive). A lot of people are left homeless, and the population as a whole is starving due to the lack of food.
• Hiccup rejecting Mirabel. It hurts both of them (him believing that she doesn't deserve someone like him, her not knowing why he'd so cruelly reject her), and leaves Mirabel in tears.
• Stoick finally realizing that he drove his son away due to years of neglect and abuse from the community.
• When the kids go to Berk to slay the Red Death, the rest of the Madrigals struggle to cope. There's an entire chapter of Tear Jerker moments dedicated to the coping (or lack thereof) methods of the Madrigals.
• Hiccup and Stoick's talk in the cove. It's written in a style very similar to Mirabel's and Abuela's talk by Pedro's river. And the two are equally heart-breaking.
• Those moments after the battle where everyone thinks Hiccup is dead. While anyone who saw the first movie knows that he's alive, it's still hard to read everyone (especially Mirabel and Stoick) reacting to his "death".

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