[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/cbfa1e4a_241f_4f1d_becd_45bb2b35d404.jpeg]]

->''Our actions define our legacy.''

Fives and Jesse are facing a court-martial and execution for disobeying General Krell's orders. Captain Rex tries to persuade Krell not to go through with it, but Krell instead orders the two troopers' immediate execution. But after the would-be firing squad refuses to go through with killing their own brothers, Rex faces a choice between his duty to follow the General's orders and his loyalty to his fellow clones as it becomes clear that the nearest enemy is ''not'' the Umbarans...

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!!Tropes:

* AlliterativeTitle: "Carnage of Krell" certainly fits sound-wise.
* AndThenWhat: At the end of this episode, a dejected Rex and Fives discuss the war. When Fives attempts to cheer Rex up by pointing out that the war will eventually end, Rex wonders what will happen to all the clones once it does. Fives doesn't know, and cannot think of anyone who does.
* AntiMutiny: Captain Rex leads the 501[-[[superscript:st]]-] and the 212[-[[superscript:th]]-] to arrest Jedi General Pong Krell when it becomes clear that Krell has turned to the Dark Side and is working to undermine the Republic's forces on Umbara, having started by tricking the 501[-[[superscript:st]]-] and the 212[-[[superscript:th]]-] into attacking each other. Rex tells his men beforehand that what they're about to do could be considered treasonous.
* ArcVillain: General Krell serves the role as the true antagonist of this story arc after the Separatist Alliance.
* AssholeVictim: Let's face it, Krell really had his death coming.
* BadGuysDoTheDirtyWork: Once Captain Rex captures General Krell, he plans to execute him to prevent him from being freed by the Separatists, but cannot go through with it. Dogma ultimately pulls the trigger for him.
* BattleInterruptingShout: Rex does this after he discovers that his men are shooting at other clones, running into the fight yelling for everyone to stop firing and take off their helmets.
-->"Everyone, stop firing! We're shooting at our own men! They're not Umbarans! They're clones! Take off your helmets! Show them you're not the enemy! They're clones! Everyone, stop firing! Cease fire! They're not Umbarans! They're clones! Look! We're clones! We're all clones!"
* BigWhat: Rex and Dogma each give one when they realize they've been shooting at other clones.
* BittersweetEnding: Krell is killed for betraying the Republic by Dogma (who still goes to jail for being supportive of Krell earlier) and the Republic has secured Umbara, meaning the planet is back on their side. Woohoo! Rex, however, isn't in the mood for celebration because one, so many 501[-[[superscript:st]]-] clones were killed taking Umbara, and two, he's now left wondering about the point of the Clone Wars.
* BoomHeadshot: Tup captures Krell with a stun blast right to the head, after the vixus smacks him around enough to get him to stop moving.
* BreakThemByTalking: Krell tries this on Rex when he sees that the captain is hesitant to execute him, but [[KilledMidSentence Dogma isn't having any of it]].
* BringIt: During the battle against General Krell, Tup stands next to a vid us and lures Krell towards it by shouting "Hey, ugly! Come and get me!" at him. Krell charges Tup and promptly steps on one of the creature's tentacles, which immediately grabs him.
* BrokenPedestal: Dogma does ''not'' take Krell's reveal that he's a traitor well and lashes out when they're in separate cells.
* CallBack: Dogma is warned to avoid stepping on one of the vines lying on the ground, with Tup pointing out that it's actually a vixus' tentacle and that he saw Hardcase attacked by one just like it (in the first episode of the arc, "[[Recap/StarWarsTheCloneWarsS4E7DarknessOnUmbara Darkness on Umbara]]").
* CallForward:
** When Captain Rex leads a squad to attempt to arrest Krell, the entire sequence and the nature of their actions are strongly reminiscent of both Order 66 and Mace Windu's attempt to arrest Palpatine in ''Film/RevengeOfTheSith''. Krell even says, "It's treason, then" before tearing into his would-be captors, just as Palpatine will before doing the same.
** Krell claims to have "foreseen" that the Jedi will lose the Clone Wars and the Republic will be "torn apart from the inside", and of course, this comes to pass in ''Film/RevengeOfTheSith''.
* ChekhovsGun: A vixus, a [[CombatTentacles combat-tentacled]] ManEatingPlant, attacked Hardcase and Fives in "[[Recap/StarWarsTheCloneWarsS4E7DarknessOnUmbara Darkness on Umbara]]", the first episode of the arc. In this episode, Tup uses one to lure Krell into a trap.
* ColourCodedForYourConvenience: Played straight and subverted. The clone troopers are members of the 501[-[[superscript:st]]-] and thus wear blue, and the "enemy Umbarans" wearing stolen uniforms wear yellow. Except the "enemies" are actually clone troopers from the 212[-[[superscript:th]]-] Attack Battalion, and both sides have been told the other were impersonators so they would wipe each other out.
* DeathGlare: Rex and Krell end up briefly exchanging mutual ones, complete with Krell getting right up in Rex's face just before the faked transmission about "disguised Umbarans" comes in. One wonders what would have happened if not for the timely interruption...
* DiesWideOpen: The 212[-[[superscript:th]]-] Attack Battalion clone that Rex unhelms to discover that his men are shooting at other clones.
* DramaticDrop: Dogma drops his helmet when he realizes that he and his squadmates were killing their own brothers.
* DramaticIrony: Krell accurately foresees that the Jedi Order won't survive the Clone Wars, but his response is to try and ally himself with Count Dooku, whom the audience is aware will meet his end even before the Jedi.
* DramaticUnmask: During the battle with the "Umbaran infiltrators", Rex sees one of their bodies with his helmet slightly ajar. He pulls it off, and finds a dead clone's face looking up at him.
* DressingAsTheEnemy: Krell tricks the 501[-[[superscript:st]]-] and a platoon of the 212[-[[superscript:th]]-] into fighting each other by making them both think they're facing Umbarans who are using this tactic with stolen clone armor and weapons.
* DualWielding: General Krell, being a four-armed Besalisk, dual-wields double-bladed lightsabers.
* EntertaininglyWrong: Krell foresaw the downfall of the Jedi and the rise of a new order, but his belief that Dooku will be a part of that new order is mistaken, though Krell isn't in any position to know better.
* EvilAllAlong: Krell fell to the Dark Side sometime before the events of this story arc. His entire campaign was designed to deliver Umbara into the hands of the Separatists to ingratiate himself to Count Dooku and become his new Sith apprentice. Foreshadowed obliquely by him having been put in charge in the first place thanks to Palpatine recalling Anakin, making him and his role already suspect by association.
* EvilLaugh: Once General Krell admits that he's a traitor, he laughs deeply in almost every following conversation.
* FaceHeelTurn: General Krell is revealed in this episode to have undergone this trope. He once was a genuine Jedi, but sometime in the past offscreen, turned evil.
* FailedASpotCheck: Fives doesn't notice that Dogma has grabbed his sidearm until after Dogma has shot Krell dead.
* FiveSecondForeshadowing: If you listen closely during the firefight in the woods, you can tell that the dying cries of the "Umbarans" are actually those of clone troopers, even before Rex figured it out.
* ForTheEvulz: Once General Krell admits that he was a traitor, Captain Rex asks him why.
-->'''Krell:''' Because I can. Because you fell for it. Because you're ''inferior''.
* FriendOrFoe: Krell invokes it by separately getting both the 501[-[[superscript:st]]-] and part of the 212[-[[superscript:th]]-] to believe they're going after a force of Umbarans who have stolen clone armor as disguises, so they believe each other to be the enemy when the two units meet before Rex finds out the truth.
* GeneralFailure: {{Subverted}}. As it turns out, Krell isn't incompetent. He's intentionally sabotaging the Republic's efforts on Umbara so he'll have a good accomplishment to present to Dooku when he defects to the Separatists.
* GodzillaThreshold: Realizing that General Krell ordered two squads of clones to kill each other convinces Rex that enough is enough, and he declares his intention to arrest the general for treason.
-->"From this point forward, we are entering uncharted territory. My orders are, we arrest General Krell for treason against the Republic."
* GoodCounterpart: Subverted. While his reckless tactics, BloodKnight attitude of victory at any cost, and racism toward the clones made his goodness questionable from the start, Krell was at least supposedly on the side of the Republic--but like Grievous, he essentially fights with four blades thanks to having four arms, and he accomplishes this by employing a pair of double-bladed lightsabers like those Darth Maul used. This actually ends up being {{Foreshadowing}} of his being EvilAllAlong, and his intention to both become a Dark Side apprentice and specifically serve Dooku as a Separatist makes him even more like Maul and Grievous.
* HeKnowsTooMuch: Rex's justification for ordering Krell's execution; the Umbaran forces are retreating towards the base, and if they overrun it, Krell could be rescued and give them vital Republic intel.
* HeroicBSOD: Rex has a brief one after finding out his men were killing other clones after being tricked by General Krell into thinking that they were disguised Umbarans.
* {{Hypocrite}}: Krell is indignant that Rex and his troops "dare to attack a Jedi". After being captured, he admits that he no longer considers himself a Jedi, but clearly still wants the respect afforded to one.
* IFightForTheStrongestSide: Krell admits that his treachery is based on the ([[VillainHasAPoint accurate]]) belief that the Jedi are doomed to lose the Clone Wars. He intends to make a place for himself among the Separatists and the Sith.
* InformedAbility: Much talk is made about how General Pong Krell's tactics are very effective, but every command he issues throughout the Umbara arc leads to defeat that his clone troopers need to reverse by disobeying his orders. Even the opening narrations of the previous episodes describe him as reckless. It turns out he was deliberately sabotaging the Republic advance prior to his planned defection to the Separatists.
* JumpingOffTheSlipperySlope: Krell initially seems to be sacrificing clones for the good of the Republic, but then he tricks them into killing each other and reveals himself as a Separatist and Sith supporter.
* JustFollowingOrders: Dogma tries to claim this mindset as justified for the clone troopers by their Kamino programming, no matter what Krell's orders are (after the latter had claimed any clones who wouldn't do so must therefore be defective). Jesse and eventually Rex refuse to accept it, saying the clones have minds of their own that can choose what they do and why--and must.
* KilledMidSentence: General Krell.
-->'''Krell:''' Eventually, you'll have to do the right thing and– ''[Dogma shoots him]''
* KilledOffForReal: Waxer and General Krell.
* LaserGuidedKarma: Shortly after deeming Dogma "the biggest fool of them all", Krell is shot dead, mid-gloat, by said fool.
* LawfulStupid: Dogma continues to support Krell, even after finding out he ordered clones to kill each other. It's only when Krell confirms his treachery and mocks Dogma for his UndyingLoyalty and BlindObedience that he snaps out of it.
* LineInTheSand: After the UnfriendlyFire incident, Rex gathers the surviving 501[-[[superscript:st]]-] and 212[-[[superscript:th]]-] clone troopers into a line, and announces his intention to arrest General Krell for treason against the Republic. He offers them all a chance to OptOut, none do.
* LowerDeckEpisode: This episode is presented entirely from the perspective of Rex and the other clones of the 501[-[[superscript:st]]-]. Unlike the previous episodes of the arc, neither Anakin nor Obi-Wan even make an appearance.
* MauveShirt: Waxer, who was given a lot of focus and likeability back in "[[Recap/StarWarsTheCloneWarsS1E20InnocentsOfRyloth Innocents of Ryloth]]", dies in the friendly fire attack.
* MoleInCharge: General Krell, though he's not actually working for the Separatists ''yet''; by Krell's own admission, his efforts on Umbara are meant to prove his worth to Dooku so he can become his new apprentice.
* MyGodWhatHaveIDone: Though Rex doesn't say this, the look on his face after he finds out his clone troopers have been killing their comrades spells it out. Tup makes it explicit.
-->'''Tup:''' This can't be happening. What have we done?
* PunctuatedForEmphasis: "I said on. Your. ''Knees.''"
* SarcasmFailure: Jesse, usually a DeadpanSnarker, has this to say on the prospect of being executed on Krell's orders:
-->"I've officially lost my sense of humor."
* ShootTheDog: Rex decides that Krell must be executed to stop him leaking critical military secrets, which would allow the Separatists to win the war very easily. It's ultimately Dogma who pulls the trigger, though.
* ShutUpHannibal: Dogma kills Krell with Fives' blaster while Krell tries to taunt Rex for his unwillingness to execute him.
* SillyRabbitIdealismIsForKids: General Krell claims that he's no longer naïve enough to believe in the ways of the Jedi, which is why he's planning to betray the Republic and defect to the Separatists.
* SingleTear: Waxer dies shedding one.
* SmugSnake: Pong Krell. He gloats about his actions even when at the mercy of his men, and when Rex has a pistol aimed at him, Krell taunts him about his inability to pull the trigger. He's actually surprised when Dogma shoots him mid-monologue.
* SpoilerTitle: Knowing the title beforehand, Krell's EvilAllAlong reveal and the carnage he causes in both the friendly fire incident and the effort to arrest him aren't quite as surprising as they should be. Although it could be justified by the results so far of his "incompetence."
* SuperWindowJump: Krell leaps out of the picture window in the control tower in an impressive shattering of glass, landing on the tarmac below, after killing or stunning the troopers who confronted him.
* TheyCallMeMisterTibbs: When Rex finally decides that General Krell is going too far in his treatment of the clones, he affirms that he's to be addressed as "Captain", not CT-7567 or "clone".
-->'''Krell:''' You are making a mistake by crossing me, clone.\\
'''Rex:''' It's Captain... ''sir''.
* ToBeLawfulOrGood: A large part of the clone troopers' struggle throughout the arc. In the end Rex chooses the latter and is backed up by the rest of his men--except Dogma. Who then still gets to do the right thing by killing Krell for having violated the law.
* TyrantTakesTheHelm: The Umbara arc opens with Anakin being recalled to Coruscant and General Krell being given command of his clones. He immediately begins to denigrate the clones, insulting their laboratory origin, exclusively referring to them by their identification numbers, and giving them horrible tactical orders. It turns out that it was all intentional: he's planning to defect to the Separatists and wants to degrade the Republic war effort before he does as a gift to Dooku.
* UndignifiedDeath: Not long after boasting of his lofty goals and while mocking Rex, General Krell is killed when Dogma, whom Krell mocked as "the biggest fool of them all", shoots him InTheBack while Krell is down on his knees.
* UriahGambit:
** General Krell's horrendous battle tactics are revealed to be part of his plan to sabotage the Republic advance in preparation for his defection to the Separatists. By giving his clones impossible assignments, they would be easily defeated and ultimately wiped out by the Separatist droid armies.
** When Rex has clearly had enough of him and starts questioning orders too much, Krell sends him and a detachment of 501[-[[superscript:st]]-] clones into an ambush, by other clones no less.
* VillainHasAPoint: No one present is aware of it, but Krell is right about the [[Film/RevengeOfTheSith impending downfall of the Jedi Order]] and the rise of [[TheEmpire a new order]].
* WhamLine: A dying Waxer delivers one, revealing that General Krell set two battalions of clones against each other, planning for them to all be killed.
-->'''Rex:''' Tell me who gave you the orders to attack us.\\
'''Waxer:''' It... it was General Krell. He sent us to these coordinates to stop the enemy. We thought they were wearing our armor. But... it was... you...
* WhamShot: The point during the firefight in the woods where Rex notices a dead "enemy" combatant whose helmet has partially come off, revealing a chin that doesn't look like it belongs to an Umbaran… and when he goes up to the body and takes the helmet off, the corpse is that of another clone trooper.
* WhoDares: Pong Krell when Rex and the clones attack him.
-->'''Krell:''' You dare to attack a Jedi?!
* TheXOfY: "Carnage '''of''' Krell".
* YouFool: General Krell decrees that Dogma was "the biggest fool of them all" for his BlindObedience.
* YouWouldntShootMe: When Captain Rex is going to execute General Krell, Krell taunts him over his inability to pull the trigger and his inherent weakness. Too bad for him that Dogma is there to pull the trigger.

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