Abhorrent Admirer: Pepé Le Pew in most (if not all) of the cartoons he was in (though there were times when the roles were reversed and Pepe became the hunted; and the only cartoon where he wasn't an Abhorrent Admirer was Arthur Davis's "Odor of the Day"); Daffy Duck in Frank Tashlin's "The Stupid Cupid"; the Mama Bear in "Bugs Bunny and the Three Bears"; and the portly Slavic-accented female bunny Millicent from "Rabbit Romeo."
Pepe and the cat are special cases; the cat freaks out at his interest mainly because he's a skunk, with all the attendant odor problems. When the tables are turned (often from Pepe either having his stench covered or removed), her attitude flips around as well and she becomes even more aggressive than Pepe was, intimidating him.
Absurdly Long Limousine: Done in a lot of shorts. Often the gag would be further reinforced with a secretary or switchboard operator at the halfway point of the limousine.
Bennie: Are ya gonna show me how to catch mouses in the warehouse, George? Are ya? Sylvester: Okay, so we're gonna catch mouses in the warehouse. And stop callin' me George! My name is Sylvester. Bennie: But I can't say Sylvester, George. Sylvester: Okay, so I'm George.
Accidental Athlete: Happens to Cool Cat in Bugged by a Bee. Subverted in that the bee gets all the credit in the end and not Cool Cat.
Activation Sequence: In "Compressed Hare", Wile E. Coyote activates a 10-billion-volt electromagnet (to catch Bugs Bunny after he eats a fake metal carrot). It takes several seconds to power up the magnet, including activating what appears to be a power generator.
Actor Allusion: Bugs Bunny mentioning Cucamonga is a reference to when Mel Blanc was the announcer on Jack Benny's radio show and would shout, "Train leaving on track five for Anaheim, Azusa and Cucamonga!". It's funny because that's physically impossible for a single train to do.
Adaptation Species Change: There's a short where Goldilocks is a mouse and the Three Bears are replaced with the Three Cats (Sylvester and his family).
Agony of the Feet: In "Cheese Chasers," Hubie and Bert, hell-bent on ending their own lives after eating too much cheese, hit Claude's foot with a hammer, trying to provoke him into eating them.
Alan Smithee: There were a few shorts where the director was left uncredited, but not because the work was so bad that the director wanted nothing to do with the project (even Norm McCabe put his name on his cartoons, despite revealing that they were awful years later). The uncredited Looney Tunes cartoons were mostly due to the director having been fired or quit and WB Studios at the time had a rule stating that only those who were employed were allowed to have their names in the opening credits of the shorts.
There are at least two cartoons that have a true Alan Smithee credit. Both directed by Friz Freleng. "Hollywood Daffy", Freleng refused credit on after Mike Maltese presented the story and gags. Freleng felt the cartoon was too wild and crazy to suit his own style (something Bob Clampett would have directed), but was obligated to direct it anyway. This is why the cartoon has no director's credit. Freleng also isn't credited on "Dough for the Do-Do", a color remake of Bob Clampett's "Porky in Wackyland". Freleng felt it was based on Clampett's idea, and he felt it would be plagiarism if he credited the cartoon as his own.
A correspondent at Facebook says that Freleng was suspended for a month after a run-in with the Warners front office over "Hollywood Daffy" and his refusal to direct it. Hawley Pratt wound up directing it.
1942's "Crazy Cruise" is uncredited; Tex Avery started it, but was fired after the "Heckling Hare Ending" incident. Robert Clampett finished it. Avery is also uncredited on the banned cartoon "All This And Rabbit Stew," which he directed.
Frank Tashlin goes uncredited in "Hare Remover" (1945). He went under "Frank Tash" and "Tish Tash" in his earlier cartoons.
1934's "Those Were Wonderful Days" and "Pettin' in the Park" both credit then-regular musical director Bernard Brown as the actual director of the cartoons, which virtually everyone involved with the studio back then denies was even remotely the case. The most commonly accepted theory is that these were actually the first two cartoons directed by Frank Tashlin, but he had quit the studio (temporarily; he returned the following year) before they were released, resulting in Brown being credited for whatever reason.
Bob Clampett's final short, 1946's The Big Snooze, didn't credit him. However, it's been widely known that he directed it (and even if it wasn't, you could still tell it was his' pretty easily.)
Alcohol Hic: The tunes use Mel Blanc's very recognizable, comic hiccup when a character is drunk - most notably in "High Note", where the drunk note hiccups throughout most of the short as he stumbles around.
Alien Invasion: Bugs accidentally causes an alien apocalypse on Earth at the end of "Hare-way to the Stars".
Bugs: Run for the hills, folks, or you'll be up to your armpits in Martians!
Alliterative Name: Most, if not all of the Looney Tunes characters (Bugs Bunny, Daffy Duck, Road Runner, Porky Pig, Cool Cat, etc).
All Just a Dream: The ending of "Smile, Darn Ya, Smile!", parodied in "The Mouse That Jack Built", plus "Water, Water, Every Hare", "Scrap Happy Daffy" and "The Wearing of the Grin".
"Scrap Happy Daffy" was more of an "Or Was It a Dream?", considering Daffy wakes to find the goat and a group of nazis stranded at the top of his scrap heap.
"The next time you dream, INCLUDE US OUT!"
"A Cartoonist's Nightmare", as suggested by the title.
"A Waggily Tale" plays with this; Junior wakes up from his nightmare of being a dog and is relieved. He goes to hug his dog, who tells the camera, "That's okay with me, 'cause I'm not a dog, neither. I'm really another little boy having a dream."
In "Fresh Hare", Humphrey Bogart asks waiter Elmer Fudd for an order of fried rabbit. Elmer tells him that they're fresh out of rabbit, but Bogart grabs him by the collar and gives him one hour to get him that rabbit, or else.
Animation Bump: Just about all of Chuck Jones early shorts, which often have very tight, solid animation (especially shorts like Old Glory) especially in contrast to the other directors. Bob Clampett shorts (once he was handed Tex Avery's unit in the 40's) also had some of the most lavish animation in the studios history, and Tex Avery's shorts were already undergoing this in the early 40's.
Going in the opposite direction, the animation generally became less nuanced after the brief shutdown of the studio in 1953, due to tighter budgets. Bob McKimson's unit suffered the most; during the shutdown, nearly his entire animation staff, most of them inherited from the Clampett unit, jumped ship, leaving him with less experienced animators who would just inbetween McKimson's layout poses and leave it at that, rather than go the extra mile and push the actions further, as Clampett animators like Rod Scribner or Bill Melendez would.
Anticlimax: "The Wild Chase" is about Speedy Gonzales and Road Runner racing each other. The cartoon ends with Sylvester and Wile E. Coyote crossing the finish line instead.
Art Evolution: The earliest shorts had a very strong Disney influence in their animation (no surprise, considering the studio was founded by Harman and Rudolph Ising, as well as Friz Freleng, all of who were former employees of Disney) but in the mid to late 30's Tex Avery and Bob Clampett slowly but surely began trying to veer off into a less Disney like cartoon style. Chuck Jones initially did VERY Disney like shorts with his Sniffles cartoons, until he decided to drop the saccharine stuff and do funny cartoons-and while Bob and Tex had already abandoned most of the Disney-esque art by the 40's, Chuck Jones and Robert McKimson personal art styles wiped out any remaining trace of the original Disney influence that was clinging to the studio at that point.
Character-specific example: Speedy Gonzales, in his 1953 debut, looked much different than the version by Friz Freleng's unit in 1955. The latter design (which downplayed the visual stereotypes like buck teeth and greasy black hair) stuck, and is the one most people remember today.
Robert McKimson's unit went through a significant art evolution; when he started directing in 1946, his characters had a lot of girth. Around 1950 or 1951, his unit began to slim the characters down; Bugs, for example, actually began to look like the model sheet McKimson himself had created.
Artifact Title: The Merrie Melodies series used to be reserved for the cartoons that were just animated musicals with thin, simplistic plots (in an attempt at copying the "Silly Symphonies" series from Disney). By the late '30s, Merrie Melodies began to feature cartoons that weren't centered around advertising a song from the WB music library. The name difference became even more meaningless in 1944, when Looney Tunes (originally a black and white series) fully switched to color, and recurring characters also began to be used in Merrie Melodies as well. By then, the only difference in the two series was the title and theme music. In fact, Friz Freleng outright commented on the fact that he never initially knew whether the short they'd be creating was a Merrie Melody or a Looney Tune, and it didn't matter anyway.
Lampshaded in Chuck Jones biography "Chuck Amuck", where when he discusses how people have told him that his characters are "realistic", he compares the characters to their real life counterparts, ending with Tweety compared to a real canary, with Jones sheepishly admitting that the only similarity he was able to find being that they're both birds.
In "Southern Fried Rabbit", Yosemite Sam claims to be holding the Mason Dixon Line, not letting any 'Yankees' across it. When Bugs tells him that the Civil War is long since over, Sam says he's no clock watcher. Later on, he catches some Yankees, but they're actually the New York Yankees — though they were in Chattanooga—so perhaps they were a Yankees minor league affiliate.
The short "Daffy Duck and the Dinosaur", with a caveman set along a dinosaur.
Art Shift: "Bartholomew versus the Wheel" isn't drawn in the typical style (looking more like something from Harold and the Purple Crayon).
Neither is "Senorella and the Glass Huarache," which seems to resemble a mid-60s or '70s De Patie-Freleng cartoons. (Not much of a surprise, as many De Patie-Freleng staff members worked on this short.)
Look at any number of Freleng's cartoons of the 40s and 50s and you'll see contrasting animators styles within each film. In The Wabbit Who Came to Supper (1942) you'll see Jack Bradbury, Cal Dalton and Gerry Chiniquy's styles (Bugs' face in each cartoon is wildly inconsistent); in "Show Biz Bugs" (1956) has Chiniquy, Virgil Ross and Art Davis' styles (less jarring).
Bob Clampett's cartoons even more so, to the extent that Clampett would intentionally play up the contrast of Rod Scribner's loose, wild animation and Robert McKimson's more subtle, Disney-like animation.
As Long as It Sounds Foreign: Hitler's speech in Russian Rhapsody which includes bizarre references to Friz Freleng, Heinrich (German version of Henry) Binder (Henry Binder was one of the associate producers of WB cartoons when Leon Schlesinger was there), "What's Cooking, Doc?", someone named "Tim O'Shenko"note A pun on the name of the Soviet general Semyon Timoshenko, who was the "People's Commisar for The Defense of the Soviet Union" at the time of Hitler's invasion in 1941 (he was replaced early on by Joseph Stalin himself taking over), ordering saurkraut from a delicatessen, and the chattanooga choo-choo (a shout out to the classic big band tune from the 40's).
The whole premise of the 1943 short "What's Cookin', Doc?". Bugs assumes he's going to win an Oscar, but it ends up going to James Cagney instead. Bugs tries to convince the Academy to give him the Oscar instead.
Also seen in the 1955 short "This is a Life?". Daffy assumes the program will be a retrospective about himself, when instead it's about Bugs.
"Little Red Riding Rabbit" sort of has one too, in which by the end of the short, even Bugs is getting tired of Red Riding Hood's constant interruptions. He then switches the Big Bad Wolf, who was about to fall onto red hot coals because of all the furniture Bugs threw on him, with Red. Bugs and the Wolf, arms around each other and sharing a carrot, watch proudly as Red soon gets what she deserves.
"Tortoise Beats Hare", "Tortoise Wins by a Hare", and "Rabbit Transit". Though Bugs could also be considered the bad guy, considering how much of a jerk he was to Cecil Turtle in the first place.
Although never shown actually eating his prey, nearly every Henery Hawk short ends with him carrying off Foghorn Leghorn so he can eat him.
Bait-and-Switch: In Hare Remover, Elmer Fudd is trying to create a Jekyll & Hyde formula and tests it on Bugs Bunny. After going through a few seconds where it seems the formula worked, Bugs uncovers his face to reveal... his regular face. "No soap, Doc."
Ralph uses toy balloons to fly in an attempt to snatch a sheep in ''A Sheep In The Deep". Unfortunately for him, Sam has a peashooter.
Banana Peel: Examples include Tweet Zoo, To Hare Is Human, and A Sheep in the Deep.
Barbie Doll Anatomy: One of the Indians in "Westward Whoa" is only wearing a loincloth that does a poor job of covering his nether regions, but thankfully there's nothing there to see.
Bat Out of Hell: Completely subverted with the bat Sniffles the Mouse meets in "Brave Little Bat". He's drawn almost identical to Sniffles, except he has a pair of tiny wings beneath his arms and pointier ears, and he's downright Adorkable in personality.
In "The Stupid Cupid", Daffy is hit by a giant arrow from Cupid, which hits him with such force that he ends up with his beak stuck through a board. He struggles to lift his arm just to burble his lips.
Being Watched: One of many fourth-wall breakers ("Did you ever have the feeling you was being watched?").
Benevolent Genie: In "A Lad in His Lamp" and "Ali Baba Bunny". Although the first one ("Smokey") did have a thing about being summoned too many times in a row (especially when it interrupted his making out with a female genie), and the latter didn't care much for being stomped on.
Beware Of Hitch Hiking Ghosts: The ghost in the Porky Pig cartoon "Jeepers Creepers" tries to hitch a ride in Porky's police car towards the end. Porky stops, backs up and holds up a sign that says "No Riders."
Big Eater: Occurs many times. One such example is the rival chicken in "Cock-a-Doodle Duel" downing dozens of hot dogs at once.
Big Little Man: One short inverts this. Beaky Buzzard finds a small reptile peeking through some rocks. Noting that the creature seems shorter than him, Beaky tries to grab it and take it home for dinner. Turns out "Shorty" is just the small head of a huge dragon.
Black Comedy: The Chuck Jones shorts are often quite cynical and jaded in their humor, and Jones was quite fond of using Chew Toy characters such as Wile E. Coyote, and portraying his interpretations of the characters as more nasty and flawed than the other directors (such as his iconic Straw Loser take on Daffy Duck, turning Bugs into a more vengeful, passive aggressive trickster with somewhat less playfulness, creating Marvin, an alien villain who wants to destroy the earth for blocking his view of Venus, etc.). Even some of his oneshots like Fresh Airedale and Chow Hound run on this. Ironically, as the Looney Tunes franchise ran its course, Jones toned down this aspect of his cartoons to be lighter and sometimes even sentimental in tone.
"Mice Follies" has shades of this; Alice and Trixie are beaten up by a cat who's invaded their home, but because it's in the dark, they think it's their husbands, Crumden and Morton, who are furious at them for staying out too late.
Bloodless Carnage: Despite the high levels of violence in several cartoons, there was never any blood, although Bugs Bunny or Daffy Duck would sometimes cover himself in ketchup pretending that he's bleeding in order to throw off his enemies, squeeze a tomato, or pour red ink (as seen in "Hare Trigger").
Sam: (gets angry, then demurely) Why did you pour ink on my head? (gets angry again)
One particular example is in "The Whizzard of Ow", wherein during the climax, Wile E. Coyote's mode of transportation turns into a crocodile, which proceeds to bite the Coyote's nose off.
Bomb Whistle: Used to punctuate a character, particularly the Coyote, taking a long fall (though there have been exceptions).
Book-Ends: "Feather Finger" begins and ends with Daffy begging for money.
Daffy: Gifts, donations, charity... ANYTHING!
"The Ducksters" begins with Porky on a conveyor belt headed for a bandsaw; the ending turns the tables by having Daffy on the conveyor belt.
Born in the Theatre: Most Looney Tunes, classic or modern, aired in theaters before they aired on television, and they often have gags messing with the Fourth Wall of Film.
Bowdlerization: When aired on television (and sometimes, home video — usually gray-market, public domain videos; the official release videos and DVDs try to make it as uncut as possible. If there are any missing scenes, it's because some of those scenes were lost long ago), a lot of the violent and politically-incorrect scenes and gags will be altered or cut. There's a website dedicated to tracking down what cartoons were edited and what channel edited them: 
Elmer tries it again in "Hare Remover". Bugs finds the trap amusing ("My grandfather told me about these things, but I never thought I'd see one.") and decides to humor Elmer and get trapped, since he went to such trouble to make one.
Elmer uses the trap a third time in "Pests for Guests", this time on the Goofy Gophers Mac and Tosh. As soon as the trap falls, the sounds of a car driving are heard from inside, followed by a loud car crash. An alarmed Elmer lifts the box to see what happened, accidentally letting the gophers out.
Breaking the Fourth Wall: The damage done to it ranges from large cracks to pulverizing it to a fine powder. On more than one occasion, near the end of a cartoon, the film suddenly breaks, leaving the screen white. A character from the cartoon then steps out onto the white screen and says, "Ladies and gentlemen, due to circumstances beyond our control, we are unable to continue with this picture."
Breakout Character: THE WHOLE SERIES has lived and breathed this trope. It all started with Friz's Batman Gambit in 1935 to jump start Leon's ailing cartoon studio with several new cartoon characters in the short "I Haven't Got A Hat"-two pups named Ham and Ex, Kitty, Oliver Owl, Beans the Cat and Porky Pig. Porky was an instant hit with audiences, even though the studio thought for some reason that Beans would be the studio's next bankable star-but he too quickly faded into obscurity while Porky became the studio's star—THEN, two more stars broke out from Porky's cartoons-a little Daffy Duck from "Porky's Duck Hunt" and the Bugs Bunny prototype "Happy Hare/Bugs' Bunny" from "Porky's Hare Hunt", "Hare-Um Scare-Um" and "Presto-Change-O." Oh, and Bugs Bunny himself obviously.
The Tasmanian Devil, despite only appearing in five of the original shorts, became immensely popular due to later spin-offs and merchandising. Essentially nearly every mainstream character was decided this way, having usually been cast as a one-timer or side role alongside a an intended star before becoming popular with the audience.
In "Bill of Hare": When Taz is right behind Bugs:
Bugs: (to audience) Eh... did you ever have the feeling you were being watched?
Marvin the Martian, like Taz, appeared in only five of the original shorts, whom would later be prominently featured on the post-1969 material and merchandise.
Foghorn Leghorn also qualifies. He originally served a supporting role to Henery Hawk. However, it was Foghorn who got the most attention, quickly morphing the Henery Hawk series into the Foghorn Leghorn series, where Henery himself sometimes showed up as a foil to Foghorn.
Brick Joke: Lots of Looney Tunes cartoons will have gags/characters that don't really add to the story until the big punchline later in the film. A lot of Road Runner cartoons run on this (a perfect example is a retractable wall from "Stop, Look and Hasten" (1954, Jones)). An example from "Little Red Walking Hood" (1938, Avery), which had Egghead walking past the action randomly:
Wolf: Hey, bud. Just a minute, bud. Just who the heck are you anyway??
Egghead: Who, me? I'm the hero of this picture! (clobbers wolf with a mallet)
The Dover Boys has a gag similar to the "Little Red Walking Hood" one: a strange, mustached man in a sailor suit wanders through the cartoon several times, looking like a walking Big-Lipped Alligator Moment and nothing else. That is until he ends up hooking up with the girl the heroes had been trying to save the entire cartoon.
At the beginning of "Often an Orphan", Charlie Dog sees a car coming up, then adopts Puppy-Dog Eyes, remarking, "Big, soulful eyes routine. Gets 'em every time." However, the car passes by without notice. At the end of the cartoon, Porky does the same thing, and it worked for him.
The vehicle that picked him up as a dog catcher truck.
Also, in the 1991 short "Blooper Bunny", one of the outtakes involves the background music skipping the same five notes over and over.
Bugs: (to crew) Ehhhh, what's up, doc??
Yosemite Sam says "Rackin' frackin' varmint!" over and over in "Invasion of the Bunny Snatchers".
Brother Chuck: Except for Daffy Duck, a lot of Porky's old sidekicks seem to have disappeared. Anyone remember Gabby the Goat? How about Beans the Cat, Ham and Ex, and/or Oliver Owl? Oh, and what happened to Porky's love interest, Petunia Pig?
Throughout the 1930s and 40s, it seemed WB were experimenting with numerous new recurring characters and scenarios to use as a mainstream cast, as time passed the cast was narrowed down to a select few that were developed or renovated (e.g., Bugs, Daffy, Sylvester) while many other previous established characters got the shaft (e.g., Hubie and Bert, Charlie Dog). Others such as Henery Hawk and Porky himself also got taken Out of Focus somewhat, but still had minor roles on occasion.
In the 70s, Ralph Heimdahl and Al Stoffel revived Petunia for some occasional appearances in the Bugs Bunny newspaper comic strip. She was the sweet kid Robert Clampett reimagined her as, not the uppity diva Frank Tashlin created her as. She was also a regular castmember in the old Gold Key and Whitman comics for decades, along with Porky's nephew,Cicero, and both appeared in all the Looney Tunes merchandise of the era (coloring books, toys, etc.). Petunia also made a handful of obscure animated reappearances (one in "Daffy Duck ad Porky Pig Meet The Groovie Goolies" and also recently in some of the official site's flash cartoons).
Another prominent Expanded Universe character that few remember these days is Bugs's girlfriend, Honey Bunny. Honey Bunny got displaced by Lola Bunny when Space Jam came out.
In A Feud There Was, a boy mocks the hillbillies on the other side of the boundary line, prompting them to shoot "DO YA MEAN IT? onto the other side's wall. They shoot back to spell "YAS WE MEAN IT!".
In My Favorite Duck, Daffy, after finding out that duck season has opened, tries to make a shotgun-wielding Porky show mercy by holding up a white flag. Porky shoots, instantly putting holes in the flag spelling "START PRAYING DUCK".
The title card for the first Bunny & Claude cartoon We Rob Carrot Patches is spelled out with bullet holes.
In "An Egg Scramble", bank robber Pretty Boy Bagel looks out the window of his hide out and tells the cops that they can't get him. The cops fire at the window, leaving "Wanna bet?" in bullet holes on the window shade.
Bulletproof Vest: Daffy Duck advertises one in The Stupor Salesman adding, "Guaranteed to get your money back if it fails to work!"
Similarly, in the Duck Dodgers short where he meets Marvin the Martian, he has a disintegration proof vest that was indeed not disintegrated by Marvin's gun. Unfortunately, the rest of Daffy was not so lucky...
Butt-Monkey: Almost every single character falls victim to these two very painful tropes. Some, like Bugs Bunny, Tweety, and Roadrunner are smart enough to stay out of harm's way (though not always); others, like Daffy Duck (the greedy narcissist, not the manic screwball), Porky Pig, Elmer Fudd, Yosemite Sam, Sylvester, and Wile E. Coyote are the worst offenders.
The Porky Pig cartoon "Who's Who In The Zoo" (1942) concludes with an ice cream truck and its vendor being flagged down by a zoo's lion who presumably wants an ice cream bar. The vendor walks out of the scene towards him. We hear the lion roar, then we see the lion with a Balloon Belly and the vendor's hat, licking his lips and giving out with a very satisfied hiccup.
1943's "Puss 'N' Booty" starts off with house cat Rudolph hiccupping out the feathers of the last bird he ate. At the conclusion, when Rudolph turns up missing, his owner asks new bird Dickie Bird where he is. He says he doesn't but then he hiccups out Rudolph's ribbon.
Butt Sticker: in the cartoon "Rabbit Punch" Bugs Bunny lifts the Champ over his head, but can't hold him up for long and is crushed. When the Champ sits up, Bugs is flattened on his back.
The Cameo: Bugs Bunny at the end of "Porky Pig's Feat" (in his only black and white appearance, no less), "Crazy Cruise," "The Goofy Gophers" and "Duck Amuck." Foghorn Leghorn at the end of "False Hare." Daffy at the end of "Sahara Hare" and "Apes Of Wrath." Elmer at the end of "Rabbit Rampage." Tweety in "No Barking" and "Heir Conditioned." Pepe Le Pew in "Dog Pounded."
Captain Ersatz: Foxy the Fox and Roxy the Fox from the first three Merrie Melodies shorts, who were very obviously patterned after Mickey Mouse and Minnie Mouse (he's even the page image for Captain Ersatz), but with pointier ears and a bushy tail. Walt Disney got wind of the ripoff and forced Rudy Ising to stop using the character. Foxy was immediately replaced by the character of Piggy note unrelated to the kid from "At Your Service, Madame" and "Pigs Is Pigs" for two shorts.
Can't You Read the Sign?: In A Day at the Zoo when a lady feeds the monkey a banana. The monkey scolds the lady "Can't You Read?" and points to the sign that reads "Do not feed the animals!"
Card-Carrying Villain: In some of the 30's shorts, especially the ones with Porky Pig as the protagonist, the series tended to fall back on generic, one-note villains whose only purpose was to be complete menaces to anyone they encountered, including such punny cyphers as I. Killum ("Polar Pals") Nick O'Teen ("Wholly Smoke") Ali Mode ("Little Beau Porky"), Boris Karloff (a burlesque of Frankenstein's Monster and Boris Karloff in "Porky's Road Race") the legion of cartoon bad guys in "A Cartoonist's Nightmare", Mr. Viper from "Milk and Money", and so on. As the franchise progressed and characters more willing to dish out more than they took like Bugs Bunny came about, the use of such clear-cut villains was downplayed in favor of more shaded, but still arrogant, wrongheaded or just plain dimwitted villains just begging to get their just desserts, such as the momma's boy Killer/Beaky the Buzzard, ill-tempered man child Yosemite Sam, the sociopathic but oddly polite Marvin the Martian, or the haughty Giovanni Jones. Many shorts just dropped the idea of having villains at all and just had the characters in playful or ridiculous conflict with each other (i.e. many of the Foghorn Leghorn shorts, where Foggy and Barnyard Dawg's rivalry stems from the loudmouthed schnook's attempts to prove to the bratty Henery Hawk that the dog is a chicken and not him, Wile E. Coyote's and Sylvester's fanatic and ineffectual attempts to catch the Road Runner and Tweety, etc.).
Casanova Wannabe: Pepé Le Pew (often mixed in with Handsome Lech). In a subversion, Pepe does succeed in catching his unwilling target, whether implied (as seen in the endings to "Wild Over You," "A Scent of the Matterhorn," "Touche and Go," "Heaven Scent," "Two Scents Worth," and "Louvre Come Back To Me") or directly stated/shown (as seen in "The Cat's Bah" and "Scent-imental Over You")
Catch That Pigeon!: Or in this case, roadrunner, canary, rabbit, duck, white-striped black female cat, Mexican mouse...
Cat Stereotype: Sylvester is the codifier for the unsuccessful black and white cat stereotype.
Cats Are Mean: Ironically, Warner Bros. was much more egalitarian about this trope than other studios like Disney. Outright subverted in shorts like "The Night Watchmen", "We, The Animals Squeak", "Fresh Airedale", "Chow Hound" and the Porky/Sylvester trilogy.
Caught in a Snare: Foghorn Leghorn sees Henery building a snare trap and points out how a smart chicken like him would just jump over it... which is just what Henery wanted, as the spot Foghorn lands is where the trap door was.
Chameleon Camouflage: A gag in "Unnatural History" involves a chameleon who proudly showcases his ability to change his color over any background. Then, he comes to plaid and breaks down.
Character Focus: Because he's a spotlight-stealer by nature (literally, in one case), most adaptations post-1960 are less about the whole Looney Tunes ensemble and more about Daffy Duck finding himself!
Chased Off into the Sunset: Played straight in the 1934 Merrie Melodies short "The Miller's Daughter". At the end of the cartoon, the lady of the house angrily lashes out at the cat, thinking it had broken a lamp. The two statues watch with pleasure as she chases the cat out of the house and into the distance.
Porky may exist as the only consistent example that rarely brings it upon himself.
Chirping Crickets: Occurs in "Show Biz Bugs" after Daffy dances to "Jeepers Creepers" and the audience is silent.
Christmas Special: 1979's Bugs Bunny's Looney Christmas Tales, which featured three shorts: "Bugs Bunny's Christmas Carol" (featuring Yosemite Sam as, who else, Scrooge), "Freeze Frame" (a Road Runner short set at wintertime), and "Fright Before Christmas" (a Bugs/Taz short). The first and last segments were directed by Friz Freleng, while the Road Runner short was by Chuck Jones.
There was also a modernized speical called Bah, Humduck! A Looney Tunes Christmas, which is A Christmas Carol but with Daffy as Scrooge.
Cigar-Fuse Lighting: In "Catty Cornered", Sylvester the Cat hides Tweety under an empty can. When the mobster Rocky finds Tweety under the can, he lights a firecracker with his cigarette and places under the can for Sylvester to find.
Circling Birdies: Often the result of falling anvils, falling boulders, mallet hits, falling pianos, fights covered up by the big, dusty ball of violence. Birdies don't always circle around the character's head — sometimes it's stars, sometimes it's brightly-colored dots or orbits, sometimes it's something completely different (like kings as seen in 1949's "Rabbit Hood.")
Clip Show: "His Hare-Raising Tale", "This is a Life?", "Feather Bluster", "Tweet Dreams", "Hare-Abian Nights", and "Freudy Cat".
"Devil's Feud Cake" was probably the most blatant of all, as it contained very little original footage — it was actually a drastically cut down version of an episode of The Bugs Bunny Show.
Clothes Make the Superman: Subverted in "Fast and Furry-ous" (Wile E. Coyote wears a superhero outfit, only to learn the hard way that just because you wear it doesn't mean it grants you the ability to fly). Lampshaded in "Goofy Groceries," "Super Rabbit" and "Stupor Duck."
Although batman capes do allow Sylvester, Sam, and Wile E to fly at different points - but don't protect them from collisions of course.
Clothing Reflects Personality: The premise of "Bugs' Bonnets": Every time a new hat blows onto Bugs or Elmer, they change their personality to reflect the hat.
Cloud Cuckoo Lander: Daffy, especially in the earlier shorts. Even later he isn't the most stable of beings at times.
The demented flying fish in the Porky Pig film "The Sour Puss" certainly qualifies.
And literally, with the Dodo.
Some non-Tweety cartoons had Sylvester showing signs of mischievous irrationality (Back Alley Oproar, Doggone Cats, Kitty Kornered).
Clown Car Base: Sam's wood-burning stove holds a 1950s New Years' Eve party (and, in a later clip show, a late 1970s disco party), in "Rabbit Every Monday".
Coattail-Riding Relative: In "Hare Trigger", Bugs Bunny briefly hides from some rabbits waiting alongside the railroad tracks.
Bugs: '"A few of my poor relations. They're always ready for a touch."
Cold Opening: While not a cold opening in the strictest sense, many Road Runner shorts from the late '50s and early '60s (particularly "Beep Prepared" and "Hopalong Casualty") featured a bit of action before the title of the cartoon was displayed.
There's also "Porky's Romance", in which an introduction to Petunia Pig is made before the title card is shown. She keeps tripping over her lines and becomes increasingly desperate.
In another Sylvester and Tweety cartoon, after various failed attempts to catch Tweety, Sylvester decides to swear off birds, after which a flock of birds perch themselves on Sylvester's shoulders. The cat gripes, "Sufferin' succotash! What a fine time I picked to go on a diet!"
"Could Have Avoided This!" Plot: In "Bee-Deviled Bruin" and "Bear Feat", Mama Bear tries to inform Henry of something, but Henry keeps shouting at her to "shut up". If he hadn't shut her up and let her talk, the plots would have been avoided.
In "Bugs Bunny and the Three Bears", Bugs flirts with Mama Bear to escape harm from the other Bears. But he does too good a job, and she becomes the Abhorrent Admirer and eventually has her way with him resulting in this trope.
In "The Super Snooper", the Femme Fatale turns out the lights and we hear kissing noises. When Daffy Duck turns them back on he has lipstick marks all over his face which she gently wipes off.
In "A Gander at Mother Goose", a cartoon based on various children's rhymes, features a segment with Jack and Jill. When the narrator gets to the part about Jack falling down the hill, nothing happens. He repeats the line a few more times before Jack rushes back down, his face smeared with lipstick, tells the narrator to forget about going up the hill to fetch a pail of water, and rushes eagerly back up the hill.
The trope also happens at the end of "Katnip Kollege" during the iris out when Kitty Bright covers Johnny Cat with kisses leaving lipstick marks on him.
Every cat painted with stripes (Penelope Cat, Sylvester, etc.) experiences this when Pepe Le Pew encounters them smothering them with kisses.
Cranium Chase: On the short "Mouse Menace", a robot cat loses its head. It feels around for it but picks up a toaster and puts it on for a while before eventually stumbling into its own head.
Crying Wolf: In "Westward Whoa", Ham and Ex the pups pretend Indians are attacking Porky, Beans the Cat and the other settlers. After a lecture from Beans, they try it again, but end up getting attacked by an actual Indian. None of the adults believe them when they run back to the camp that they're attacking—until the indians start firing arrows at them anyway.