- Watching Nathan get mistreated by Rebecca Nightrod in "Girlfriendklok" can be rather painful to watch, especially for those who have gone through abusive relationships.
- The whole premise of "Dethdoubles", if one looks at it that way. In that episode, Dethklok hires a group of similar-looking decoys to protect them from dying, but they grow so attached to them that they refuse to let them go. They even offer to burn themselves after their decoys are injured by a volcanic eruption because they are afraid of losing the only friends they had. What makes this episode more heartbreaking is the fact that Dethklok is completely unaware that their decoys are Tribunal agents, which makes for potential Fridge Horror when you think about how lonely these guys must feel due to their celebrity status.
- In "Rehabklok", Pickles faces being replaced unless he sobers up. The way his voice goes from anger to desperation is heartbreaking.
Replace me? Don't replace me! Please don't replace me!
- In the same episode, it's revealed that why Pickles is The Alcoholic of the band is that his older brother Seth wrongfully framed him for burning down their father's garage, and it's implied that Pickles has also been subjected to emotional abuse by his entire family. You'll never see him drinking the same way again.
- "Doublebookedklok". Offdensen is so occupied with his work that he completely ignores Dethklok in the process. The band starts to believe he hates them and after they are yelled at, they run away in despair on the day of an important concert. The lengths Dethklok goes to get Offdensen's attention borders very much on this, especially for people who experienced Parental Neglect.
- Especially heartbreaking are the genuinely sad expressions on Dethklok's faces when Offdensen turns down the band's offer to spend the weekend off with them. When you see someone like Nathan Explosion look like a child being told that their parents are too busy to play with them, you can't help but cry along with them.
- For Skwisgaar fans, "Fatherklok" can be rather heartbreaking. After spending his entire life without any father figure, Skwisgaar is told by his mother Serveta to come meet his father; he assumes she is referring to his birth father whom he has never known, only to find that she was referring to his new stepfather Týr, whom Serveta has just recently married. Skwisgaar and Týr eventually warm up to each other as father and son, but then the two of them walk home together after a heartfelt conversation and find Serveta in the exact same siutation that made Skwisgaar runaway when he was young (a threesome with two men). Týr cannot accept her infidelity and leaves her, which ruins the father son relationship Skwisgaar finally almost got to have. To further drive in the nail, it is possible to see Skwisgaar's accepting the possibility of divine heritage as a way of coping with the Parental Abandonment he feels towards his birth father, as gods do not stay on Earth and raise their children.
- The Reveal about Toki's childhood was absolutely horrendous and heartbreaking to the point where it brought many Metalocalypse fans to tears. To explain, Toki was born in an abandoned town in Norway, where the only people living there were just him and his parents. Aslaug, a priest of some unknown religion, was a complete douchebag to Toki, making him do backbreaking chores such as carrying heavy logs and cleaning up the snow with nothing but a straw broom, all at a very young age. When Toki didn't do it right, he was slapped, whipped to the point of permanent scarring, and imprisoned in a dark and deep cellar for indefinite periods of time (which led to his phobia of bicentennial quarters). The effects of living such a life as Toki did were subtle, but there - in "Dethfam" and "Dethdad", Toki goes catatonic at the mere thought of visiting his home again; in Fatherklok he says that he came to peace with his father's death, despite feeling guilt over the whole thing, and in the same episode he is seen visibly shaking after Nathan slaps him hard to snap him out of his excitement over Skwisgaar's absence. This adds new levels of Adult Fear and Harsher in Hindsight to Toki's childish behavior, especially for those who also have a child of their own. It's no wonder that many fans thought Aslaug deserved it when he drowned after Toki (accidentally) dropped him into an icy pond with a hole in it.
- The end of "Bookklok". Even though Skwisgaar has consistently treated Toki like crap, the lengths he goes to save him during a panic attack as well as the desperation in Skwisgaar's voice makes the scene tearjerker-worthy.
- "Diversityklok". In previous episodes, Murderface's And Zoidberg status within Dethklok has always been Played for Laughs. But this episode in particular shows that to be left out of something just because someone doesn't like the way you look is painfully Truth in Television. Thanks a lot, Toki!
- Nathan apologizes to Pickles. in "Church of the Black Klok". You can actually feel the regret in Nathan's voice and the fact that he vomited blood from his mouth just to say "I'm sorry!" is a sign of the sheer emotional stress that he felt in the face of apologizing to his friends, manager, and acquaintances who saw him as an asshole for what he did with Abigail.
- In "Going Downklok," the moment Nathan realizes that Abigail used him to pleasure herself after her vibrator died and then dumped him when she was finished, right in front of his best friend Pickles (who wanted Abigail from the start) was pretty sad. What made it even more sad? In "Klokblocked", Nathan spent the entire episode looking for a girlfriend he can love and appreciate, only to have his meddling bandmates ruin ever single one of his relationships. This put some level of Foreshadowing and Harsher in Hindsight so when Nathan tried to "go down" on Abigail, he believed that he had found the perfect partner, only for that partner to use him like a tool and throw him away once he wasn't useful anymore. It didn't help that this would later put a significant wedge in Nathan's friendship with Pickles, who due to Green-Eyed Monster would come to see him as a selfish asshole and leave the band.
- Magnus reflects on his life with Dethklok, before he was kicked out.
- Abigail's Lullaby. Not even the Lyrical Dissonance joke could ruin how damn beautiful this is.
- I Believe, a song about Toki celebrating his new life and family with Dethklok, and things are only on the up and up... then cut to a shot of Toki beaten up and half-comatose in Magnus's prison at the very end, knowing that Dethklok is not making an effort to save him and refuse to call him their brother when that is the only thing keeping Toki afloat in that hell.
- Do It All For My Brother where Edgar sings a heartfelt duet with his deceased brother, about how they'll do anything for the other.
- Despite its rather cheerful animation and lyrics, Partying Around The World will hit you right in the gut. The lyrics tell about Dethklok's way of dealing with their grief over witnessing Toki and Abigail's kidnapping by the Revengencers. Their friends' absences hurts them so much that they completely deny Toki and Abigail ever existed, and they constantly hold parties just to keep themselves occupied.