Wham! Line/Western Animation

"Warhawk: (to John Stewart) Dad?"
 * Justice League Unlimited: "And if I were you, I wouldn't probe the situation too closely...rich boy."
 * The last line in "Once and Future Thing, Part 1".

"Terry: (To Bruce Wayne) "My point is I just found out that Warren McGinnis isn't my father! You are!""
 * From the final episode, "Epilogue" (It also counts as one for Batman Beyond).

"Optimus: "All right, it's time. Computer, prepare to blow the pod doors." Computer: "Negative. Pod doors are magna-sealed." Optimus: "That's... impossible." Megatron's voice comes out of nowhere over the speaker: "Oh. I assure you. It is not." Moments later... BOOM!"
 * The Spectacular Spider-Man: "After all, we know who you love the most...bro."
 * "Guilty, guilty and oh so guilty of being the new Big Man of crime!"
 * In the first season finale of Beast Wars, Optimus is piloting a stasis pod set to self-destruct towards this big planet-destroyer. The plan is for him to blow the doors and zoom out before the explosion.

"Optimus: Well that's just prime."
 * "Coming of the Fuzors, Part 2" sees the Maximals about to be destroyed by the Predacons. Cue a Big Damn Heroes moment from an unexpected source.

"Shaggy: "There's only one thing missing from your theory, Fred: the creep inside!""
 * What's New, Scooby-Doo? has a Wham! Line in its pilot episode, that subverts expectations from previous incarnations of the franchise:

"Queen of the Crown: "I know all about you, Ranger Foxx." (as the Slaverlord behind him takes on the form of his wife) Senator Whiner: "Walsh! I know where Gooseman's genetic models came from.""
 * Adventures of the Galaxy Rangers:

"Slade: Trigger? There is no trigger, because there is no detonator."
 * Teen Titans, episode "Apprentice Part I":

"Robin: It's about time we came face to face."
 * Even earlier than that, when the audience learns Red X's identity in Masks:

"Slade: You're going to destroy the world, Raven..."
 * And in Birthmark:

"Zhao: I assure you, I have everything under control. I intend to remove the moon as a factor. ("Siege of the North, Part 2") Iroh: You have two grandfathers, Prince Zuko. Fire Lord Sozin was your father's grandfather; your mother's grandfather was Avatar Roku. ("The Avatar and the Fire Lord")"
 * Avatar: The Last Airbender:

"Korra:"
 * From The Legend of Korra: "When Extremes Meet".

"Prospector: I tried reasoning with you, Woody, but you keep forcing me to take extreme measures."
 * Toy Story 2:

"Lotso: Where's your kid now, Sheriff?"
 * In Toy Story 3:

"Lotso: Family man, huh? I understand. Put him back in the time-out chair."
 * And before that:

"Finn: We must've left millions of dollars back on that beach. What's the matter with you, Big V? Shendu, possessing Valmont's body: Valmont cannot hear you right now."
 * "What do you mean, escape?"
 * Metalocalypse: "That's my bread and butter you're fucking with."
 * Tom and Jerry: The Movie: "The name is Puggsy. What's yours?"
 * Jackie Chan Adventures season 2 episode 1 episode "The Stronger Evil" has this exchange:

"Mayor Fred Jones Sr.:"
 * Fred Jones from episode 26 of Scooby Doo Mystery Incorporated: "Mystery Incorporated is dead."
 * Moments before that:

"Scott Tenorman: I'm glad you like [the chili] so much, because now that you're almost finished I have something to tell you. Cartman: What? You mean about how you put pubes in your chili?"
 * South Park: "I. Can't. Die."
 * "You're Getting Old": "Because I'm unhappy, okay?! I've been unhappy for a long time!"
 * "Scott Tenorman Must Die":

"Cartman: Do you like it? Do you like it, Scott? I call it "Mr. and Mrs. Tenorman chili"."
 * And later:


 * In "201", The Reveal of the Head Ginger's identity is directly preceded by this line:

"2003 Shredder: BEHOLD! A MULTIVERSE of accursed Teenage Mutant Ninja Turtles!"
 * In one of the most memorable scenes of Turtles Forever, what started off as a simple crossover movie escalates into a Crisis Crossover with this:

"Kim: But...We captured the Supreme One. See? (gestures to Dr. Drakken and his cohorts) Rufus 3000: Where? I don't see her. Kim: Her?"
 * Kim Possible: A Sitch In Time

"Eric: "Actually, here I'm known as Synthodrone 901.""
 * And from So The Drama

"Alt!Doofenzchmirtz: Platyborg...Do that same thing to those two boys over there.
 * From Phineas and Ferb The Movie: Across the 2nd Dimension:

Regular!Doofenschmirtz: What?"

"Zhalia: I can't blew my cover until Klaus says so."
 * Huntik Secrets and Seekers

""Just for old time's sake, let's...play "uncle"."
 * From near the end of "Ed, Edd 'n' Eddy's Big Picture Show":

"Darkseid: Savor your moment of triumph, Superman, but remember--victory has its price."
 * Superman the Animated Series

"Jafar: It's mine! It's all mine! I-- Where is it? No! NOOOOOOOOO!!!"
 * Aladdin:

"Aladdin: It's the truth! Why don't you believe me? Jasmine: Because we know you're lying!"
 * And in Return of Jafar:

"Optimus Prime:"
 * Transformers Prime:

"Ned Flanders: Now calm down, Nedilly-diddly-diddly-diddly-doodly, they did their best, shodilly-iddly-iddly-diddly. Gotta be nice, hostiddly-iddly-diddly-diddly... AW, HELL-DIDDLY-DING-DONG-CRAP! CAN'T YOU MORONS DO ANYTHING RIGHT?!"
 * Adventure Time: "Hello. My name is Simon Petrikov."
 * The Simpsons episode "Hurricane Neddy":

"Scott Summers/Cyclops: (pulling Professor X from his wheelchair) It was YOU! YOU did this! Professor X: (laughing, as Mystique's voice emerges) Yes, I did it. (Professor X changes into Mystique) Mystique: And now, it's about to get much worse."
 * X-Men Evolution: In "Day of Reckoning" Part 2

"Trask: You can't make me do this! You were designed to protect humans from mutants! Master Mold: That is not logical. Mutants are human. Therefore, humans must be protected from themselves."
 * X-Men: "The Final Decision"

"Twilight: I'm sorry...
 * The first part of the My Little Pony Friendship Is Magic second season finale, when Twilight believes she messed up:

You will be."

"Twilight: "Princess Celestia invites you to the wedding between Princess Mia Amore Cadenza and... my brother!?""
 * And before that in the same episode:

"Red Tornado:"
 * Young Justice: "Auld Acquaintance"

"Bart Allen: ".""
 * And from "Happy New Year",
 * From "Bloodlines":

"Nightwing:"
 * Subverted nicely, in "Depths".

"Nightwing:"
 * And

"Superman: Good luck, my friends, I'm sorry I can't join you. Black Vulcan: We understand, Superman, this is one mission that would be much too dangerous for you.""
 * For context,
 * From the "Super Powers Team" incarnation of Superfriends, the episode "Darkseid's Golden Trap":
 * Even the Narrator is puzzled at what sort of mission is so dangerous that Superman himself has to sit it out;