Phineas and Ferb Lost Episode is a creepypasta based on a lost episode for Phineas and Ferb (in particular, an alternative episode to "Phineas and Ferb Get Busted!").
The story can be found here: https://lost-episode-pastas.fandom.com/wiki/Phineas_and_Ferb_Lost_Episode
This creepypasta contains examples of:
- Adaptational Villainy: Doofenshmirtz plans to bomb the Tri-State Area with an atomic bomb, and attempts to kill Perry with a gun, only to end up killing Phineas instead. In canon, he's very much a Laughably Evil Ineffectual Sympathetic Villain who pulls a Heel–Face Turn in the series finale.
- And There Was Much Rejoicing: Everyone who's still alive is happy that Doof is going to die, partly because he killed Phineas, and his death led to the deaths of Candace and Jeremy.
- Bloodier and Gorier: In the original, no characters ever died onscreen. Here, Phineas, Candace, Jeremy and Doofenshmirtz all die.
- Driven to Suicide: Candace, after Phineas' death. Jeremy is mistakenly believed to have murdered her.
- Fan Disservice: There's a sudden flash of Vanessa passionately making out with her mother at one point for no apparent reason.
- I Love the Dead: For some reason, Jeremy kisses Candace's corpse after discovering that she'd hanged herself.
- Killed Offscreen: Jeremy's death is never shown. It's implied that Linda killed him, seeing as she thought he had strangled Candace to death, though it's also possible that he was tried and executed like Doofenshmirtz.
- Mistaken for Murderer: Jeremy is mistakenly thought to have murdered Candace, who actually committed suicide.
- My Life Flashed Before My Eyes: As Doofenshmirtz is being executed, he has flashbacks to Vanessa's childhood, represented in live-action. It's promptly rudely interrupted by a sudden appearance of Vanessa and her mom making out.
- Nightmare Face: Doofenshmirtz has one when he chases Perry.
- See Slasher Smile below.
- Red Eyes, Take Warning: Dr. Doofenshmirtz has these when he confronts Perry and mercilessly pursues him.
- Shamed by a Mob: After Doofenshmirtz kills Phineas, the crowd that came to see the flying car and airport tower glares at him, horrified at what he'd done.
- Slasher Smile: Phineas and Ferb's parents, Ferb, Isabella, Baljeet, Buford, Charlene Doofenshmirtz, Vanessa, Major Monogram, Carl and Perry are all described to have "twisted and sick smiles with the purest, unhealthiest, sadistic joy" during Doofenshmirtz's execution.
- Smash Cut: From Linda screaming "Jeremy...how could you?", thinking that Jeremy strangled Candace to death, to Doofenshmirtz on the electric chair.
- Villains Want Mercy: Doofenshmirtz asks for mercy before he's executed. However, Major Monogram shoots it down and orders Perry to turn on the electric chair.
- Villainous Breakdown: When Perry finds Doofenshmirtz, the latter draws a real gun and opens fire against him, chasing him with a totally complete demented and cruel, angry expression and red eyes. He also comes very close to killing Perry many times, and only fails because Perry dodges his bullets.
- Would Hurt a Child: While Doofenshmirtz killing Phineas is just unintentional, we're left to assume if he felt guilty or not.
