This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Boatmurdered
The pathetic injured puppy near the beginning inspired someone to keep all pets in a safe cage with a food supply in their fortresses from then on.
Guerrilla Burialgears' final departure from Boatmurdered, as narrated by Evilslug:
The fortress of Boatmurdered burns, without and within. All is smoke and fire. Everybody is dead, save two. I ask you to picture a lone, abandoned child and the well-known madman Guerilla Burialgears outside the heavily decorated mountainside entrance.
The child plays in a bone pile, simpleminded and happy. She seems oblivious to the death and decay that surround her on all sides. Once a celebrated hero, Guerilla Burialgears has found himself helpless as this idiot child when he was needed the most. The would-be ruler silently mourns for the poor child's future while he knowingly and selfishly prepares to leave her behind. As he pulls on his pack and begins searching for the road, the girl suddenly yells "SHINY!" and thrusts a pebble toward him. Guerilla reaches out to take the smooth stone and rubs it thoughtfully between his fingers while returning an empty smile. The girl quickly goes back to her bones and he takes the opportunity to leave.
This is all he knows to do. Killing her would be a service, but his swords seem too heavy for the task. Or is it his heart? He once more rubs the stone and decides this is how it must be. He simply cannot kill her. One of the greatest dwarven warriors to ever live, unable to kill a child. He would find it pathetic and laughable, were he still sane.
Alas, his very soul is broken, along with his mind. The famed dwarven warrior now finds himself too emotionally weary to do more than mindlessly pilot his body toward safer fields or a pitiful and uncelebrated death. After a bit of searching, Burialgears finds the outline of the main road and begins to follow it toward civilization. The only coherent thought he can seem to muster will ultimately become his mantra and his sole reason for continued life in the early months of his upcoming journey: "Any place is better. I must press on."
I ask that you picture this dwarven champion pausing briefly atop the last ash-encrusted ridge in the distance. In the waning light of a setting sun, he looks back upon the gaping, smoking maw of hell's door one last time. At this moment, he finally sees Boatmurdered for what it truly is; a wicked and foreboding blight upon the surrounding lands. The windswept and charred landscape robs him of any tears he might have produced. All are dead at Boatmurdered. The best dwarves he has ever known...gone. In his mind, the blood of the dozens he could not save will eternally stain his hands. In his head, he will forever hear the screams of the dead as they burned or murdered one another in the last days of the once-proud fortress.
Guerilla Burialgears absently tucks the child's rock into his pack and turns to leave for good; his head hung low. His words trail behind him as he disappears over the ridge. It is a haunting whisper, quickly stolen away by the wind: "All burn...".
And then he is gone.
High atop the cliff, a lone child waves goodbye and chases her gesture with the kind of carefree laughter only youth can enjoy. She then returns to her game with a pair of pretty stones, almost immediately forgetting about the nice dwarf in the shiny suit. This unfortunate young girl will come to be known in legend as "Dodok Sabrefrenzies, last survivor of Boatmurdered". In all cultures, both name and place will come to elicit hushed tones and ultimately grow to be synonymous with doom of the very soul, itself.''