History YMMV / TheFlash2014

** [[AdaptationalVillainy The Trickster]], real name James Jesse, is a bloodthirsty [[TerroristsWithoutACause terrorist]] with a flair for the dramatic and the [[PsychopathicManchild personality of a deranged child]]. After a killing spree that landed him in prison, the Trickster is [[Recap/TheFlash2014S1E17Tricksters introduced]] by breaking free from prison with the help of his son Axel, who he manipulated and groomed into becoming as dangerous a psychopath as him. With his help, the Trickster takes Henry Allen hostage and tries to have him impaled with knives while also poisoning the guests at a party so he can blackmail them into giving him money, with one guest dying as a demonstration. During his [[Recap/TheFlash2014S2E9RunningToStandStill second appearance]], the Trickster uncaringly abandons Axel and teams up with Mark Mardon/Weather Wizard for a chance to kill the Flash. And to do so, he disguises himself as a mall Santa and distributes over a hundred gift-disguised bombs to children, and forces the Flash to let Mardon torture him to death on threat of detonating the bombs and killing the children and their families.
** [[Characters/ArrowverseHunterZolomon Hunter Zolomon]], aka [[EvilCounterpart Zoom]], is a sociopathic speedster from Earth-2 who was a notorious serial killer with a staggering body count both before and after becoming a speedster. Dying from abusing the Velocity drug, Zoom tries to steal the speed of Jay Garrick, the Flash of Earth-3, before taking Jay's identity to [[HopeCrusher create hope so he can crush it]], while imprisoning the real Jay as a trophy. Discovering Earth-1, Zoom sends meta-humans to attack, then gains [[Characters/ArrowverseBarryAllen Barry Allen]]'s trust by pretending to be Jay. In their first confrontation, Zoom breaks Barry's spine and shows him off for the city to see. Zoom also takes Harry Wells's daughter, Jesse, hostage to force Harry into helping him steal the Flash's speed. Once cured, Zoom unleashes an army of meta-humans on Central City for the fun of it, before forcing Barry to watch as he murders Barry's father, Henry. As his endgame, Zoom makes a doomsday device to [[OmnicidalManiac destroy the entire multiverse]], only sparing Earth-1 as his personal domain. A brutal, sadistic maniac devoid of remorse, Zoom remains one of the most monstrous enemies Barry has ever faced.

* CompleteMonster:

** Some love Ralph Dibny for being funny, Hartley Sawyer's performance, being less angsty than Wally (at first) and being a protege to Barry who isn't another speedster, but others see him as a ReplacementScrappy for Wally, an out of place character in general, an annoying misogynist, and pointless comic relief with juvenile and crude humour that ruins the tone of the season, all of which isn't helped by how Ralph is portrayed as an AdaptationalJerkass. He outgrows the misogynistic aspects of his character, but his constant cycle of not wanting to be a hero only to be persuaded later, and then forget that lesson in the next episode has grated on many fans. While his hatred has subsided since he became a NiceGuy in Season 5, he is still one of the reasons why Season 4 was poorly received.

* EvilIsCool: Bloodwork has been mostly well received by the fanbase thanks to his motivations, powers and being a [[NightmareFuel genuinely frightening]] villain. [[spoiler: His OneWingedAngel form also looks extremely cool.]]

** As seasons passed, Cisco Ramon has become more polarizing with time. Some still find him funny and relatable, while others think that the writers no longer seem to know what to do with him, that he has lost the charm he had in earlier seasons and that he should be PutOnABus at this point.
** Cecile Horton fell into this hard after becoming a meta and joining Team Flash. Her haters lambasted her for being a SpotlightStealingSquad who always ends up with her powers being the PlotDevice used to solve the problems, especially in later seasons where she keeps getting more powerful and more involved. Additionally, while most fictional psychics on the side of good respect MindOverManners, Cecile, constantly uses her telepathy and empathy on others without their consent. However, her fans defend her as a strong female supporting character who gives happiness to Joe and isn't afraid to either call out Barry when she thinks he's wrong or to support him when he's down.

* MemeticMutation: ''The Cecile / The Virtue'' [[note]]Cecile's ever increasing screen-time, powers and her suddene journey to being a costumed superhero have led to jokes from the fandom that she had usurped Barry's position as the main protagonist of the series and it should be named after her.

** Apparently, Cecile's powers can reach ''across time'' now, just when that's most useful.

* DesignatedHero: While not as extreme as other examples, Nora gets hit with this in the second half of the season. In ''The Flash And The Furious'', Nora lies to the police, telling them that Joslyn broke out of police custody when she was actually kidnapped, possibly making her prison sentence longer, all because she found out Thawne had been lying to her and [[InsaneTrollLogic that must mean no criminals can change]], despite being told by someone who can feel emotions that Joslyn felt guilty about what she did. While she does come to her senses about Joslyn, in ''Memorabilia'' not only does she ignore Sherloque's warnings about not using the memory machine alone, risking the lives of herself, her parents and Grace, so she can continue to lie about working with Thawne, but we also learn that she's something of an UnreliableExpositor regarding her previous claims about Iris being a bad parent. She also tricks Sherloque into falling for a meta so he will be more focused on stopping Cicada instead of figuring out her secret in ''Goldfaced''. While her teaming up with the Young Rogues turned out to be a plan to steal weapons to destroy Cicada's dagger, that's no excuse for the robberies, allying her self with three different super-villains who she should have expected to betray her, and for threatening Cisco in a way that manipulates his trauma. Plus everyone else on Team Flash was [[EasilyForgiven very forgiving considering she was working with their arch-enemy for months and lying about it and for the crap she pulled in ''Gone Rogue'']].

* ReplacementScrappy: ''Khione''. Caitlin fans despise her because she not only replaced Caitlin, but she also effectively sinks the Snowbarry ship. Fans who dislike Caitlin hate her because she takes time away from other characters, and pretty much everyone dislikes how she also serves as an excuse to keep [[TheScrappy Chillblaine]] around because he plays a large role in her creation. Which ends up being pointless when he leaves halfway through the season. She also doesn't play much of a role in Team Flash; she's not a fighter, journalist/detective, or engineer, doesn't appear to have any of Caitlin's medical knowledge, and doesn't have any other relevant abilities other than undefined powers and a "connection to nature," meaning that throughout Season 9 she either doesn't play a significant role in most episodes, or else uses her powers perfectly tailored to the plot to save the day.

** Reverse Flash, Zoom, Savitar, and Godspeed all return for the GrandFinale. Sadly, [[{{Jobber}} they all get defeated very quickly and easily (by side characters) almost as soon as they show up]].

* WTHCostumingDepartment: In 2049, Allegra, Chester, and Cecile look pretty much exactly the same as they do in the present day, implying that, either the show didn't bother with any aging makeup, or else that sometime in the next 20 years they'll start using a Lazarus Pit or something. Cecile (who ought to be in her 60's, at least, and doesn't show a single grey hair) even lampshades this.

* AssPull: Apparently, Cecile's powers can reach ''across time'' now, just when that's most useful.

* NarmCharm: The team hug at the end of episode 7. Is it a bit cheesy? Yeah. But it also shows the bonds of friendship between all of them.
* ReplacementScrappy: ''Khione.'' Caitlin fans despise her because she not only replaced Caitlin, but she also effectively sinks the Snowbarry ship. Fans who dislike Caitlin hate her because she takes time away from other characters, and pretty much everyone dislikes how she also serves as an excuse to keep [[TheScrappy Chillblaine]] around because he plays a large role in her creation. Which ends up being pointless when he leaves halfway through the season. She also doesn't play much of a role in Team Flash; she's not a fighter, journalist/detective, or engineer, doesn't appear to have any of Caitlin's medical knowledge, and doesn't have any other relevant abilities other than undefined powers and a "connection to nature," meaning that throughout Season 9 she either doesn't play a significant role in most episodes, or else uses her powers perfectly tailored to the plot to save the day.

* TearJerker: Whatever your feelings about latter-day Flash, any longterm Arrowverse fan would have to be made of stone not to be moved by [[spoiler: Barry and Diggle seeing Oliver one last time]].

* WTHCostumingDepartment: In 2049, Allegra, Chester, and Cecile look pretty much exactly the same as they do in the present day, implying that either the show didn't bother with any aging makeup or else that sometime in the next 20 years they'll start using a Lazarus Pit or something. Cecile (who ought to be in her 60s at least and doesn't show a single grey hair) even lampshades this.

* MoralEventHorizon: The Reverse-Flash passed this long ago. First, he traveled back in time to [[WouldHurtAChild kill a young Barry Allen]], but failed thanks to interference from the Flash. Instead, he settles on [[KickTheDog killing Barry's mother]] then leave. Since he's TrappedInThePast, he kills Wells' wife for no reason, takes the genetic code of the real Dr. Wells, and causes all the disasters in Central City on purpose, with complete disregard for all the lives of others. All so he can get revenge on Barry and steal his speed for [[ItsAllAboutMe himself]].

* MoralEventHorizon:
** Lewis Snart put a bomb in his own daughter's head to make his son work for him.
** Zoom's first appearance on Earth-2 was to fake a call about hostage situation and kill 14 out of 15 cops that came to rescue them. The last one was spared to tell the tale and when he did, Zoom murdered him too.
** In "Running to Stand Still," the Trickster and Weather Wizard pass out hundreds of bombs ''to children'' all across the city by disguising the Trickster as [[BadSanta Santa Claus]]. When the Flash discovers this, the two gleefully laugh about how they will blow up multiple families if the Flash doesn't let them beat him to death slowly.
** Deathstorm's casual admittance that he hasn't let Martin Stein [[AndIMustScream out in years]].
** Zoom's father murdering his wife while making his young son watch.

* MoralEventHorizon:
** Grodd's attempt to nuke Central City permanently establishes how far beyond sympathy he is. Even Caitlin, who had shown affection for Grodd and was even something of a MoralityPet for him, flat-out says that there's no good left in him.
** Savitar killing Iris in the BadFuture just to hurt Barry is already horrible enough on its own, but after TheReveal it becomes even more atrociously evil; he didn't just murder some innocent woman for his own gain, he murdered ''his own fiancée'' simply to spite his younger self and ensure that he becomes a villain.

* MoralEventHorizon: Clifford [=DeVoe=]'s possession of an innocent man and incrimination of Barry was heinous, but the line was crossed when he become abusive to his wife and created a loop in which he drugged her with The Weeper's tears to keep her seduced and whenever she discovered the truth, he would wipe her memories. Basically he put the one person he loved in a fate worse than death. His irredeemable status is made more apparent when Barry and Ralph find out that [=DeVoe=]'s good side is literally dead.

* MoralEventHorizon: Any pretense that Future Grace Gibbons can be redeemed goes out the window when she stabs her uncle Orlin InTheBack, killing him. This is what establishes her as a NotSoWellIntentionedExtremist.

* MoralEventHorizon:
** As the episode title suggests, "There Will Be Blood" really marks the point where the MadScientist Ramsey Rosso truly becomes the supervillain Bloodwork, when he murders several people at a hospital, turns them into zombie drones, and then absorbs their dark matter infused bodies into himself in a mad attempt to stave off his cancer forever and effectively achieve immortality.
** While Eva [=McCulloch=] was shown to be a SympatheticMurderer [[spoiler:when she kills her husband]], she becomes less sympathetic when [[spoiler:she frames Sue for said murder]].

* ReplacementScrappy: ''Khione.'' Caitlin fans despise her because she not only replaced Caitlin, but she alsoeffectively sinks the Snowbarry ship. Fans who dislike Caitlin hate her because she takes time away from other characters, and pretty much everyone dislikes how she also serves as an excuse to keep [[TheScrappy Chillblaine]] around because he plays a large role in her creation. Which ends up being pointless when he leaves halfway through the season. She also doesn't play much of a role in Team Flash; she's not a fighter, journalist/detective, or engineer, doesn't appear to have any of Caitlin's medical knowledge, and doesn't have any other relevant abilities other than undefined powers and a "connection to nature," meaning that she doesn't really play a significant role in most episodes other than some dialogue.

** People may be surprised to notice that earlier depictions of the Flash like in [[Series/TheFlash1990 the 1990 series]], ''Series/{{Smallville}}'' or the Franchise/{{DCAU}} don't generate lightning when he runs. This only started in the mid-1990s when writer Creator/MarkWaid introduced the Speed Force concept, which the show uses heavily as opposed to the others.

* ReplacementScrappy: ''Khione.'' Caitlin fans despise her because she not only replaced Caitlin, but she also [[ShipSinking effectively sinks]] the Snowbarry ship. Fans who dislike Caitlin hate her because she takes time away from other characters, and pretty much everyone dislikes how she also serves as an excuse to keep [[TheScrappy Chillblaine]] around because he plays a large role in her creation. Which ends up being pointless when he leaves halfway through the season. She also doesn't play much of a role in Team Flash; she's not a fighter, journalist/detective, or engineer, doesn't appear to have any of Caitlin's medical knowledge, and doesn't have any other relevant abilities other than undefined powers and a "connection to nature," meaning that she doesn't really play a significant role in most episodes other than some dialogue.

* ReplacementScrappy: ''Khione.'' Caitlin fans despise her because she not only replaced Caitlin, but she also [[ShipSinking effectively sinks]] the Snowbarry ship. Fans who dislike Caitlin hate her because she takes time away from other characters, and pretty much everyone dislikes how she also serves as an excuse to keep [[TheScrappy Chillblaine]] around because he plays a large role in her creation. Which ends up being pointless when he leaves halfway through the season.

** After surviving being erased from existence (twice) and then getting killed, it's hard to believe Thawne is really gone for good just because he's been erased from existence a third time. [[IKnewIt Fans were proven correct]] when Thawne was confirmed to return for Season 9.

* AngstWhatAngst: "Hear No Evil" is an episode in which Caitlin is suddenly and effectively killed off and replaced by Khione, who literally has Caitlin's body and apparently possesses some semblance of Frost's powers, but has the personality of neither, and thus Team Flash debates whether Khione should be considered her own person or whether she should be viewed as Caitlin's new personality (and thus they should attempt to restore Caitlin, even though it would erase Khione.) In the end, they elect to leave Khione as is, and the equipment needed to restore Caitlin is destroyed by Pied Piper so that Mark can't use it to restore Frost... and then the whole team decides to party, as if they hadn't justy effectively lost a close friend and one of the last remaining members of the original Team Flash.

* InformedWrongness: Most of Team Flash [[spoiler: willing to let Thawne fade from existence is treated as a bad thing, and that they should show mercy to him, but that ignores the fact that Thawne is a horrific monster who has made Barry's life a living hell since day 1--from framing his father for his mother's murder to altering history so he can rule as a hero--and he's dying of his own actions]], not because Team Flash is trying to kill him themselves. It's not crossing the heroic MoralEventHorizon so much as it it's letting a KarmaHoudini get what's coming to him. It's almost like the writers tried to create a Batman-Joker situation between Barry and [[spoiler: Thawne]] and that Barry needed to enforce ThouShallNotKill to keep from becoming a monster, yet forgot that said dynamic works because Joker ''wants'' Batman to kill him so he can destroy his efforts to protect Gotham, whereas [[spoiler: Thawne wants to make Barry's life a living hell, and even admits ''to his face'' that he won't stop doing so even when Barry offers to save him.]] The only plausible explanation for why Joe specifically objects is that, by Barry admitting he knows a way to save [[spoiler:Thawne]] and choosing not to do it, he would be committing murder-by-inaction, something an old cop like Joe would be very against.

* ReplacementScrappy: ''Khione.'' Caitlin fans despise her because she not only replaced Caitlin, but she also [[ShipSinking effectively sinks]] the Snowbarry ship. Fans who dislike Caitlin hate her because she takes time away from other characters, and pretty much everyone dislikes how she also serves as an excuse to keep [[TheScrappy Chillblaine]] around because he plays a large role in her creation.

** James Jesse telling the new Trickster that he is his father. [[BigLippedAlligatorMoment It comes right out of nowhere, serves little to no bearing on the plot and is never mentioned again.]] However, since it's Mark Hamill saying "I am your father" in a tone that makes it clear he's wanted to say that line for years, the end result is gloriously cheesy.

* Ass Pull:

** Patty's decision to leave Central City in "[[Recap/TheFlash2014S2E10PotentialEnergy Potential Energy]]", as her dream to become a CSI had never even been casually alluded to prior to this episode; [[DownplayedTrope however]], [[RewatchBonus there was a fair amount of foreshadowing. In her very first episode, she scopes out a crime scene, notes that she's read all of Barry's CSI reports, and gives him a sample, and in the following story works together with Barry to examine and analyze a corpse.]]

** Caitlin is intended to be seen as the bad guy for treating Mark with disdain. Thing is, he ''was'' a confirmed criminal whose HeelFaceTurn (in so much as it happened at all) was mostly offscreen, so it's hard for the audience not to share her views of him. Especially because he leaves Caitlin with his and Frost's bar tab, which comes off as him just being petty and proving that he's still not such a great guy. And in his next appearance, he comes in having just stolen some tech from someone else. In fact, at no point does Mark ''ever'' show any truly heroic qualities.

* CreatorsPet: By Seasons 8 and 9, some fans feel like Cecile and Allegra have [[SpotlightStealingSquad overtaken the focus]] despite being among the least popular of the regular cast due to the former reading her team's minds without their consent despite refusing to do so with her clients and being perceived as having overtaken the plot from her formerly supporting character as a lawyer and [[CharacterShilling shilled by the characters]], while the latter is regularly percieved as rather bland but excessively InFocus.