YMMV / Four Knights of the Apocalypse

• Arc Fatigue: The "Liones Battle" arc lasts for more than thirty chapters and chronicles only a single day. It vastly progresses the story, but around the time of the fifth fight in it, some readers got impatient.
• Base-Breaking Character:
  • Gawain is either loved for her funny personality, or despised as a selfish pervert who perpetuates a prejudiced stereotype. A third camp also despises her for being a pale Replacement Scrappy to Escanor.
  • The members of Tristan's Platoon have a mixed reception. On the one side, there are those who like their Nice, Mean, and In-Between dynamic and their genuine concern for Tristan's well-being, while others still can't forgive them for attacking Percival's group over a misunderstanding in their first appearance. While the opinion about Jade improved later, the same cannot be said for Isolde and Chion. There are those who like Isolde's Insecure Love Interest personality or enjoy Chion's despicable behavior, while others consider them to be annoying and irritating characters because their obsession with Tristan comes to be considered uncomfortable instead of funny. There are even those who despise Isolde or Chion so much that they wish one of them had died instead of Jade (the only one of the group who is not obsessed with Tristan).
  • Right after the release of Chapter 72, there was a large split on Jericho. Half the detractors heavily criticized her after learning her motivation for betrayal (that she was in love with Lancelot, ran away from him because she found her feelings inappropriate, and seemingly joined Arthur's side because he showed her a world where she could couple with an older Lancelot), while the other half just saw it as an extension of her inability to let go of Ban or theorize she has been brainwashed in some form by Arthur.
  • King gets mixed reactions, especially from the Japanese, for his treatment of his adopted human son Mertyl and how he handles the situation with his long-lost biological child Nasiens. On one hand, some fans believe he does care for Mertyl as much as he does for his biological children and only apparently neglects him because the joy of finding his missing first child made him forget he could have been a support Mertyl first. Other fans criticize King because he raised a human in the Fairy Realm, where the air is poisonous for humans, and had Mertyl on bitter pills his entire life while keeping him in the dark about his true heritage. He also unintentionally offends Nasiens by offering him the Drug of Yore as a gift after keeping it hidden for the two years Percival was in a coma, which can be seen as King using the drug as a way to get closer to his long-lost child rather than a genuine desire to help him revive his friend.
• Crosses the Line Twice: Lancelot's subplot in the Liones arc, involving as it does his friends getting beaten half to death by law enforcement, a twelve-year-old stealing his first kiss, demons attacking the city and beating his friends up again, and his teacher telling him with utter seriousness that she's a pedophile who's been attracted to him since he was a preteen. And also that she's fucking an alternate magical sexdoll of him made by King Arthur. At some point, the subplot feels less like a logical series of events than the result of the author thinking "How many traumas can I put this character through in one day?"
• Designated Love Interest: Anne is build up as Percival's love interest from her introduction, but fans find they have weak romantic chemistry because there's barely UST between them even after Anne gives him medicine mouth-to-mouth. It doesn't help Percival looks and acts much younger than he is, and Anne mostly treats him like a naive younger brother rather than a love interest.
• Draco in Leather Pants: Regardless of Pellegarde spending years in the service of an openly genocidal tyrant, a lot of readers put the best possible spin on his actions.
• Ensemble Dark Horse:
  • Pellegarde's paternal fondness towards the kid who's his assassination target has made him quite popular with the fanbase, despite his status as a minor character.
  • Mertyl quickly became popular among the Japanese audience even though he's a minor character who doesn't get introduced until over 130 chapters in, thanks to his hardworking Jerk with a Heart of Gold character and sympathetic backstory as the changeling adopted son of King and Diane.
• Fan-Preferred Couple:
  • Although Percival/Anne have several Ship Tease moments and are set up to be the canon main couple, many prefer Percival/Nasiens because the fans agree that their bond and chemistry is better developed.
  • Although Lancelot/Guinevere and Tristan/Isolde are intended to be canon, Lancelot/Tristan has some popularity being Childhood Friends with a Red Oni, Blue Oni dynamic, being the protagonists in Grudge of Edinburgh. It also helps that their fathers have one of the closest friendships in the previous series.
• Flip-Flop of God: Guinevere's hair color, which is purple on book covers and described as "black" in the editor's note at the end of chapter 86.
• Harsher in Hindsight: Cruder sections of the fandom used to joke that Jericho's attraction to Ban had shifted to his son. Then this actually happened. To make matters worse, what people thought Jericho was displaying as well as her being isolated with Lancelot for years already happened with another character—Vivian, who was still so obsessed with Gilthunder that she kidnapped his son, Chion. It's as if she was brought back to show that Jericho wasn't as bad as she could have been.
• Ho Yay:
  • Some interpret Chion's obsessive devotion to Tristan as having a sexual dimension to it, especially because it comes with murderous jealousy of those prophesized to fight alongside him.
  • In one scene, Percival is weirdly insistent that he wants Nasiens, specifically, to bathe with him. And when Nasiens says no, he sneaks into Nasiens' bath later anyway.
• I Knew It!:
  • Sin's true identity as a shapeshifted Lancelot was theorized by several fans, and confirmed in chapter 49.
  • Fans theorized from the start that the star-visored knight Lancelot was searching for was his teacher, Jericho, because of the cliffhanger involving the two in the prequel series. As further clues (the knight's experience with Liones, ice magic, and rose-enamelled armor) emerged, their amount grew until very few people were surprised when chapter 70 revealed it.
  • Nasiens being the long-lost child of King and Diane. Many fans had guessed it from Nasiens' introduction because his character design resembles King with Diane's hair color.
• Jerkass Woobie: Mertyl is overly distrusting of humans and acts like a big Jerkass towards Nasiens, treating him like a nuisance and wanting him nowhere near his parents King and Diane. However, his circumstances are very sympathetic and pitiful because he's actually a human who got Switched at Birth with King and Diane's true firstborn child (Nasiens), his adoptive parents kept him in the dark about him being human, and as he grew up, he was mocked by fairies for not looking anything like his adoptive family. To make it worse, the air of the Fairy Realm is harmful for humans, causing Mertyl to constantly feel sick and need to take bitter pills to continue living there, all while still not knowing what's wrong with him. Even Nasiens sympathizes with Mertyl despite the insults and beatings he has gotten from him.
• Jerks Are Worse Than Villains: Arthur is a genocidal king willing to exterminate all non human races, but the Jerkass characters in the main cast get much more hate from fans:
  • Chion is well despised for his callous disregard for the rest of the four knights, even attacking them behind Tristan's back.
  • A major reason Gawain is a Base-Breaking Character is that she would look down towards the other four knights and bad-mouth them at best, or even attack them in Friendly Fire at worst, tying into her sociopathic nature.
• Memetic Mutation:
  • The identity of Kiane's child. ^note King and Diane's child(ren), unlike the other Spinoff Babies, did not appear in the series for some time. Therefore, almost every character with a young age and unrevealed parentage was theorized to be one of them. It's eventually revealed that Nasiens is when the others show up.
  • Arthur plays Minecraft. ^note Chapter 84 revealed that Arthur has been removing vast cubes of earth from Britannia's landscape as part of his evil plan. Readers were quick to notice that the gaps left behind look exactly like those in Minecraft.
• Mind Game Ship: Lancelot and Guinevere, who has lied (or deliberately omitted important information) at least once in every interaction they've had so far.
• No Yay: There are many ships most fans aren't happy about.
  • Lancelot (16y.o)/Guinevere (12y.o) is a base-breaking ship for many reasons. One is their age gap in which she is a child while he is a young adult in-universe when she steals his first kiss. The other is how he will, according to Guinevere, fall for her despite their current age gap positions - and before she reaches her young-adult age of 16. The latter is implied by Lancelot getting nervous and embarrassed (instead of disgusted, as you might expect) when Guinevere mentions they're going to be lovers, along with Nakaba teasing their relationship on the cover page despite their current ages.
• Squick:
  • The twelve-year-old Guinevere deeply kissing Lancelot, without his consent. (He is almost as squicked out by it as the audience, immediately wrenching her off and demanding to know what she thinks she's doing.)
  • The reveal that Jericho, Lancelot's 34-year-old teacher, fell romantically in love with him when he was a boy and this is why she defected to Arthur's faction. She says he will create an alternate reality where Lancelot is closer to her age and reciprocates her love, regardless of how the actual Lancelot feels about it (which, obviously, isn't great).
  • Guinevere herself is put through the wringer when she’s kidnapped by Ironside, brought to Camelot, and the 32-year old Arthur forces her to be his bride.
  • Gawain is a very lecherous character with a small body, which disgusts many readers.
• Values Dissonance:
  • Calden's physical abuse of his daughter is treated as a brief lapse in judgment from an essentially loving father, in accordance with conservative Japanese norms.
  • Guinevere's young age makes her Forceful Kiss of Lancelot very unnerving, especially because of her refusal to accept she did anything wrong and her confidence that Lancelot will take her as his lover by the time she’s 16 years old while he will be 20. The manga is set in medieval times- where girls as young as Guinevere could be married off to older men of power, albeit nominally- but that realism doesn't make it less disturbing to Lancelot or the reader.
• Vanilla Protagonist: It's not that Percival is considered a bad character but he is a fairly straightforward Shounen protagonist with a rather generic Kid Hero personality who can come across as dull and one-note compared to the other more quirky characters around him, particularly compared to the members of his squad who have unique Hidden Depths or the fan favorites, Lancelot and Tristan.

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