Super Shredder returns to confront the turtles and their allies.
- Attack Its Weak Point: Subverted. Previously, Super Shredder's weak point was his exposed mutagen heart. However, Stockman-Fly's batch of "super mutagen" proceeded to "stabilize" his condition; the heart is now no longer his weak point, and proved to be impervious to even Karai's sword, which she found out the hard way.
- The Bad Guy Wins: Overall, Shredder clearly wins the episode, having killed Splinter, something he had being trying to achieve since the start of the show.
- Battle Amongst the Flames: Shredder and Karai's duel in the Mighty Mutanimals' burning base. Shredder remarks that it reminds him of her mother's death, and Karai nearly dies in this fire.
- Big "NO!": After Shredder tosses Splinter off the Wolf Hotel building, Leo lets out one after he hits the ground.
- Bishounen Line: Averted. Super-Shredder's "stabilized" form is identical to before, apart from the blades emerging from him being slightly longer, his eyes not glowing anymore and his previous weak point (the mutagen heart) now being invulnerable.
- Bloodless Carnage: Splinter is first stabbed then thrown off of a very high building, and his body shows no blood or carnage.
- Call-Back: At the amusement park, Bebop uses his "Turtles, come out and pla-ay!" line again, even invoking the trope by name.
- CPR: Clean, Pretty, Reliable: After saving an unresponsive Karai from the Mutanimals' burning base, Leo is able to revive her with CPR.
- The Dark Side Will Make You Forget: Shredder's love for Tang Shen, and her choosing Splinter over him, is his primary reason for turning evil. By this time, he's fallen so far that he no longer seems to care about Tang Shen at all, having absolutely zero qualms against mocking Shen's death to Karai's face by declaring that it's fitting that Karai will die in the same manner as her mother.
- Darker and Edgier: As the situation spirals out of control, the heroes resort to outright killing their enemies. Leatherhead drowns Rahzar, and the party that confronts Shredder atop the Wolf building had every intent of killing him. Casey outright tries to murder the Shredder via garbage truck trash compactor.
- Dirty Coward: Leatherhead calls out Rocksteady as this after being attacked from behind.
- Disney Death: Rahzar is dragged helplessly to the bottom of the river by Leatherhead, and Leatherhead surfacing without him and the camera focusing on this implied that Rahzar was killed. In Season 5, it's revealed that he did, in fact, die, though Kavaxas brings him back to life.
- Downer Ending: The Shredder finally succeeds at his goal of killing Splinter, and unlike the last time, it sticks, leaving the Turtles without their father. And to top it off, the Hamato Clan's own attempt to kill Shredder fails, leaving him able to menace them for the finale. Also, Karai has been seriously injured.
- Everybody Cries: The turtles all cry over the death of their beloved father and mentor, Master Splinter.
- Evil Cannot Comprehend Good: Shredder tells Splinter that his weakness is that he cares about others.
- Family-Unfriendly Death: Splinter is impaled on-screen, and then, for good measure, thrown off a building. Earlier, Rahzar is dragged underwater by Leatherhead and drowned.
- Forgot About His Powers: Karai doesn't attempt to utilize her mutant snake form during her fight with Super Shredder, even though it could have possibly evened the odds, or held him off until backup arrived.
- Hurricane Kick: Splinter pulls one off against Shredder.
- Impaled with Extreme Prejudice: Splinter, when Shredder succeeds in killing him once and for all. Note that this happened before in "Annihilation: Earth", but was undone by time travel.
- Irony: Rahzar/Chris Bradford (Mikey's would-be friend) is killed off by Leatherhead (Mikey's real friend).
- Killed Off for Real: Impaled with Extreme Prejudice, thrown off the roof, and nothing mystical in the heroes' possession to fix or undo it, it is unlikely that Splinter will be brought back to life this time.
- Know When to Fold 'Em: After seeing Shredder beat the crap out of Rockwell, Mondo Gecko decides to sit the battle out.
- Leaning on the Fourth Wall: Mikey says the series is winding down and they're at the end of the season...before holding up a VHS of Chris Bradford's cartoon.
- Make Sure He's Dead: Shredder does this to Splinter after impaling him, by tossing him off the several stories tall building.
- Mass "Oh, Crap!": All of the heroes when witnessing Splinter's death.
- Leo scream when seeing Shredder get up from his fall.
- April and Raph when seeing Shredder impale Splinter.
- The rest when seeing Spinter's body thrown off the roof.
- Meaningful Name: A requiem is a Catholic mass for the deceased. Though, it should be noted that Splinter doesn't die until towards the end of the episode, after which all four Turtles are seen carrying his corpse and grieving over his death and the funeral occurs in the next episode.
- Mythology Gag:
- Casey's crushing of Shredder in the garbage truck after a fall from a rooftop parallels the same action taken at the end of the original live action film. He also says the same line ("Oops."), albeit much more harshly and bitterly. Just like this Shredder, that Shredder’s encounter with a garbage truck failed to kill him as well.
- The Raised Hand of Survival mentioned below parallels the Shredder doing this in the second live action film. Interestingly, he did this twice, the second as Super Shredder, which, unlike this time, was subverted into a Dead-Hand Shot.
- Splinter has suffered several deaths across the mythos, though this is one of the first instances of the death sticking since the original comics.
- The villain's transformation form in Chris Bradford's show looks very similar to Carter's mutated form in the original 1987 series.
- As noted below in Where It All Began, the confrontation with Super Shredder takes place stop the Wolf building just as the first confrontation did in this series. As this arc is the last of the show before the Post-Script Season, this could also apply on a meta example considering the Wolf building is named after Fred Wolf (of the 80’s series).
- Nice Job Breaking It, Hero: Honestly, Splinter's death is partially his own fault. Splinter suggested the team to split it, to which Leo protests that its not a good idea. Splinter doesn't listen, and leaves with Raph, April, Casey and Slash, while Leo is forced to go on with Donnie, Mikey and Leatherhead. Leo's suspicions are proven true when Bebop and Rocksteady indicate that they intentionally had the team be split up. Much to Leo's horror, once he finally arrives to the Wolf building, it's too late to save Splinter.
- Raised Hand of Survival: Super Shredder's hand busts out of the top of the garbage truck he was in, indicating that he is still alive even after the fall and being crushed.
- Relative Button: After setting the Mutanimals' base on fire, Shredder declares to Karai that it's fitting that she should die just as her mother did: in an inferno. Karai promptly flies into a rage and tries to stab Shredder directly in the heart... only for her blade to shatter against it.
- Sanity Slippage: Just when you thought Shredder couldn't possibly get any more insane than he did when he became Super Shredder, he does. By now, he doesn't even care about Karai at all anymore, and tries to kill her like everyone else on Splinter's side.
- Suddenly Shouting: Shredder pulls this off after impaling Splinter in front of Raph and April.Shredder: And now, Hamato Yoshi... DIES!!
- This Cannot Be!: Rockwell's reaction when Super Shredder No Sells blasts from his laser guns.Rockwell: That's superheated plasma! Impossible!
- Took a Level in Jerkass: Annihilation Earth already proved Shredder to be irredeemable, but he somehow managed to become worse by mocking Tang Shen's death to Karai's face, implying he doesn't even care about Tang Shen anymore even though her picking Splinter is one of the reasons he turned evil in the first place.
- Wham Episode: Splinter has been Killed Off for Real.
- Where It All Began: Splinter, April, Casey, Raph, and Slash confront Shredder atop the Wolf building, where Raph notes their first confrontation with him took place. Slash declares that they'll finish him there as well.
- You Are Better Than You Think You Are: When Splinter tells Leo that he will one day be the "father" of the group, Leo has doubts, recalling that Splinter first made him leader of the team only because he asked. Splinter admits that he actually made Leo the leader because he always knew he had it in him, even when Leo was a child.
- You Can't Fight Fate: Splinter dies the same way as he did in Annihilation: Earth!; Shredder taking a cheap shot by impaling him from behind, implying this was how he was always destined to die, only the Turtles bought him some time by undoing the previous timeline.
