* BaseBreaker: [[spoiler:Yuji Sakai after merging with the Snake of the Festival]], and ''oooh boy'' is it almost as bad as [[Manga/{{Naruto}} Sasuke Uchiha]]. While he has clearly has [[WellIntentionedExtremist well]]-[[UtopiaJustifiesTheMeans intentioned]] goals, others consider him to be a borderline {{Sociopath}} who doesn't care about anything else outside of his goals.
* BrokenBase:
** The third and final season has split the fandom between supporting Flame Hazes and Crimson Denizens -- and in this case, RootingForTheEmpire is quite understandable.
** Geneon Dub VS Funimation Dub. That is all.
** Yuji's DarkerAndEdgier AntiHero tendencies over the course of season 3 has left many fans grumbling about the drastic change in personality.
*** The problem stems a lot from the anime adaptation. Yuji expresses despair over the endless, ultimately nihilistic Flame Haze-Denizen struggle very early in the light novels, as well as a growing determination to do whatever it takes to end it. The Snake of the Festival, who shows up out of nowhere with no foreshadowing or buildup at the beginning of ''Shakugan no Shana Final'', approaches Yuji from within the Midnight Lost Child [[WeCanRuleTogether and tempts him with promises of ending the eternal conflict]]. He also starts to exhibit a much more aggressive personality far sooner as well. For example, in the anime, when Wilhelmina attempts to kill him to prevent the Midnight Lost Child from falling into Bal Masqué's hands, Yuji does little to fight back. In the light novels, after Shana prevents Wilhelmina from harming him, Yuji takes the opportunity to ''try to kill Wilhelmina'', and comes close to doing so. In short, Yuji's FaceHeelTurn, for a given value of heel, is not the abrupt switch the anime made it out to be, but a well-telegraphed and logical conclusion to his character growth.
* CargoShip: Shana x [[TrademarkFavoriteFood Melon Bread]] has been shipped. Also, Shana has a WhatIsThisThingYouCallLove moment regarding melon bread and Yuji.
%%* CreatorsPet: Kazumi Yoshida.
* CommonKnowledge: Shana is the prototypical hyper-aggressive, ultra-violent {{Tsundere}} who habitually dominates and abuses her love interest. Except she’s not. While Shana introduced, [[TropeCodifier or at least codified]], a type of {{Tsundere}} that is more hot-tempered and more abrasive to her love interest, and while the hyper-aggressive, ultra-violent {{Tsundere}} can [[ShanaClone claim a direct line of descent from Shana]], she lacks the borderline abusive behavior (at worst striking Yuji all of three times in the first season-- of a three-season show—in moments that are played for laughs), tendency to treat their love interests in a subhuman fashion (Shana’s early dismissal of Yuji as a “thing” is due to the fact that, ordinarily, he would be little more than a non-entity as a Torch), and the tendency to dominate or tyrannize said love interests that they have. Shana actually is closer to the classic {{Tsundere}}, a person with harsh outward personality, the result of a sociability problem, who gradually reveals a softer and loving side. Her CharacterDevelopment is really quite remarkable, even when comparing the cold and hostile Shana at the beginning of Season 1 to prickly but friendly Shana of mid-Season 1, let alone the Shana of Season 3, who can no longer even be considered {{Tsundere}}.
* DieForOurShip: Kazumi, especially after [[spoiler:Pheles gave her a Treasure Tool which can summon Pheles, but would take Kazumi's life as a price]].
* DudeNotFunny: The ending of the ''Shakugan no Shana'' movie. [[spoiler:Yuji, believing he's going to fade, finishes what he thinks is his "last speech" to Shana just as the Reiji Maigo replenishes him. Shana and Alastor double over laughing.]]
* EnsembleDarkhorse:
** Hecate is the most popular of the main antagonists. Many were initially drawn in by her cute character design but eventually warmed up to her in season 2 where as Konoe Fumina she begins to develop human-like emotions
** Sabrac is also one of the more popular antagonists despite not having been introduced until the end of season 2. He is mostly remembered by viewers for his memorable battle, and many can back him up as the most {{Badass}} antagonist in the series. There's also the fact that unlike other villains he had a backstory to his motivations and even a rivalry with one of the main characters.
** Decarabia one of the minor villains introduced in season 3 got a lot of attention. Many were amused by his strange character design and his tendency to constantly appear at the most random of times.
* EvilIsCool: [[spoiler:Yuji as Snake of the Festival]] definitely fits the bill; his fans often nickname him as Darth Vader [[spoiler:Yuji]], or just Darth [[spoiler:Yuji]] for short.
* EvilIsSexy: [[spoiler:Yuji as Snake of the Festival]] has attracted a lot of fans over to his side because he took a massive level in {{Bishonen}}. Honourable mention goes to Bel Peol, with her choice of clothing.
* FandomBerserkButton: [[http://www.youtube.com/all_comments?v=7_mJBJWJJUk It seems the correct form of Shana's catchphrase is "Urusai! Urusai! Urusai!!!"]]
* FriendlyFandoms: With ''LightNovel/ACertainMagicalIndex''. Both are light novels published by Dengeki-Bunko that got published around the same time and have the similar concept of magic in a modern day setting, alongside a male protagonist who is partnered with a hot-headed female lead. It also helps that the anime for ''Index'' aired at the height of ''Shakugan no Shana's'' popularity and even featured many similar cast members.
* IdiotPlot: Some feel this way about Season 3, in which the Denizens are simply trying to get out the Flame Hazes' hair and avoid having to RetGone any more humans. The only reason there is conflict is because the Flame Haze army doesn't trust them.
* GodModeSue: [[spoiler:Yuji after he ascended as Snake of the Festival]]; he basically and literally becomes God, and needless to say the strongest character in the series.
* LesYay: Wilhelmina and Pheles are really good friends, but the way Wilhelmina acts when they meet is just a trace beyond that (and Wilhelmina [[TheStoic doesn't emote much towards anyone]]).
* MemeticMutation:
** URUSAI! URUSAI! URUSAI!
*** URUCHAI! URUCHAI! URUCHAI!
** OH GOD SHANA IS HOT
** [[VerbalTic de arimasu~]]
* MoralEventHorizon: To several people, Yuji driving Margery Daw towards the DespairEventHorizon, as well as the infamous scene between him and Shana during her captivity in the Palace of Stars.
* MostAnnoyingSound: ''Keisaku Sato's voice'' (his season 2-beyond [[Creator/GregAyres voice actor]] to be exact; the season 1 [[Creator/BradSwaile voice actor]] was better-sounding for him)
* NeverLiveItDown: Yuji is probably going to be forever remembered since season 3 as 'that would-be rapist world destroyer' no matter what positive qualities does he have.
* NightmareFuel: Being devoured by a Crimson Denizen results in you being replaced by a Torch. Bad enough that your remaining life is spent as a sort of cosmic scab meant to insulate the universe from your disappearance. What makes this NightmareFuel is that when the Torch burns out, not only do you die, but no one will ever remember that you existed at all. There's an episode that chronicles Yuuji trying to save a Torch; watching her run down and burn out is equal parts TearJerker and this trope. If memory serves, the episode even ends with "What have we been doing all day?" when she does vanish. Brrrr.
* ParanoiaFuel: At any time in the past, you may have been killed, eaten, and replaced with a copy ''without you even realizing it''. And eventually, that copy can run out of power...
* RootingForTheEmpire: One interpretation is that the more Crimson Denizens (Guze no Tomogara) are in desperate need of resources and thus feeding on humans is sometimes the only option and some Flame Haze are [[KnightTemplar overzealous]]. The former is backed up by the idea the Bal Masque was founded by a god, thus they essentially should have the same authority as Flame Haze (though they are not contracted with Crimson Lords). The latter is partially backed up by the fact that Margery Daw was originally shown as being somewhat of a BloodKnight and cared nothing but {{Revenge}}, thus indicating that there are more violent and less honorable Flame Hazes.
** RootingForTheEmpire became a more viable option in the later light novels (and the third season) when it is revealed Bal Masqué's plan, as well as [[spoiler: their new leader Yuji's]], is to create a utopia called Xanadu where Crimson Denizens will not need to devour humans to sustain their existence, and even coexist peacefully with them. [[spoiler: And considering how the series [[TheExtremistWasRight ends]]...]]
* TheScrappy: Kazumi Yoshida. Aside of the DieForOurShip and RealWomenNeverWearDresses factors, there's the fact that people think she's shallow, boring, clichéd schoolgirl-in-love-for-a-classmate, steals too much screentime for her little romantic-anime antics, has a formidable amount of CommonMarySueTraits and, for the final blow, her impact to the overall plot is almost null. A quick Google search turns up comments on her such as "The single greatest flaw with this series is that she isn't dead yet."
** That said, at least some people saw her as RescuedFromTheScrappyHeap after the final season.
* SeasonalRot: For a lot of viewers the first season was well-received and thought of as a great start to the franchise. However, many felt that as the show went on it got progressively worse. Season 2 was criticized for beginning on a filler arc that lasted half the season, and not doing much to differentiate itself from season 1. It was the third season where many felt that ''Shakugan no Shana'' began to lose its touch. Many criticisms were aimed at [[spoiler: Yuji fusing with the Snake of the Festival]], the introduction of many new characters that had no development and added nothing to the show with some [[spoiler: dying in their first fight scenes]] and the IdiotPlot involved in the final battle.
* {{Squick}}: The Aizens, Tiriel and Sorath, [[BrotherSisterIncest make out with each other]]. In public. A lot.
* TheyWastedAPerfectlyGoodPlot: Yuji coming to terms with his upcoming CessationOfExistence with the knowledge that at least he won't be ''completely'' forgotten when he disappears could've made for an interesting story (even if the story had to go searching for a new male lead after that). Instead, Yuji turned out to be a LivingMacGuffin that regularly restores his own Power of Existence.
* VisualEffectsOfAwesome: One of J.C. Staff's best animated adaptations in recent years, and the third season [[SerialEscalation simply escalate from there]], culminating in the glorious AnimationBump that comes with [[spoiler:the creation of Xanadu]].
* {{Wangst}}: Often resulting in combat. At times it seems like the series would be half as long if Shana and Kazumi wouldn't take so much time with their angsty internal monologues over Yuji, although Yuji himself is no stranger; he plays this trope at the end of the second season!
* WhatTheHellCastingAgency: A lot of fans (especially those who were familiar with [[Creator/BradSwaile season 1]]'s dub) didn't like Creator/GregAyres's performance as Keisaku Sato in [[TheOtherDarrin Funimation's cast]].
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