Blazing Dragons. A particular example is the allusions to the Arthur/Guinevere/Lancelot triangle of the King Arthur mythos in the case of Queen Griddle's obvious infatuation towards Loungelot. And then there's Sir Blaze.....
On the topic of Sir Blaze, the theme song/title sequence includes the knights extolling their virtues: "We're straight and true and good and kind..." Sir Blaze winks at the camera when he says the word, "Straight."
The animated adaptation of The Mask was a wacky 1990s cartoon, and therefore, was chock full of Parental Bonus and the occasional risque jokes — but...one episode stands out as the reason why American censorship (at least back in the 1990s) is considered a joke by most: season two's "Flight as a Feather," which, along with the standard Double Entendres (The Mask telling the audience that African violets weren't the only things drooping on Mrs. Peenman), your typical gross-out humor (The Mask showing an irate pizzeria customer his green, pulsating guts, and the customer nearly puking), and Parental Bonus references (the mayor implying that he blew the city budget on a party for beauty contest winners), included two scenes that kids' cartoon writers (not even most Cartoon Network writers) wouldn't dream of putting in:
The scene of Cookie BaBoom (the Mayor's suicidal ex-girlfriend who works as an exotic dancer note Smedley almost calls her a "stripper," but corrects himself. Whether or not this was a censorship measure is up for debate) rushing the stage in a trenchcoat and flashing everybody...her bikini made of explosives and holds the Mayor hostage because he broke up with her, followed by The Mask using the explosives on Cookie's body to make a drink known as The Bikini Cocktail. As if that weren't enough, just as Kellaway and Doyle go to arrest The Mask for harassing Mrs. Peenman and a customer at a pizzeria, The Mask uses Cookie's naked body to distract the cops — and it works, even on the hard-assed Kellaway, who can only stammer out "Lady, y-you're under arrest," before sliding to the floor.
What really puts that entire part over the top is the implication that this aired live and that old woman in Bavariaville saw everything (yet only freaked out over The Mask harassing the Mayor).
The performance artist at the pillow feather factory sounds like a mild, but fairly obvious gay stereotype (he has a lisp and comes off as very effeminate). To make matters worse, he's named after a brand of oil (Crisco), which can be (and often is) used as a lubricant for anal sex.
In X-Men, the episode "Time Fugitives" features Rogue calling a Friends of Humanity goon a "peckerwood," which not only sounds perverted, but is also a racial slur for a white person (particularly one who is considered "trailer trash" — uneducated, poor, violent, very close-minded when it comes to dealing with minorities and modern women, and obsessed with all that is cheap and tacky).
In one episode Rogue had to administer CPR to an unconscious Cyclops: while giving him kiss-of-life and pumping his chest she cries "Come ON, Scott, make a girl happy!"; almost like a girl on top trying to have an orgasm...
For some old school crap under the radar, don't forget Scooby-Doo. Famous are Shaggy and Scooby's not so subtle hippie tendencies, including constant "munchies" for Scooby Snacks and smoke occasionally coming out of the mystery machine. Word of God states that Scooby Snacks are just dog biscuits. That doesn't change the fact that Shaggy likes them as much as Scooby does. If anything, it only adds to his "stoner" persona since getting the "munchies" would make him want to eat anything that could be considered "edible," whether or not it's food for people.
Scooby Doo often says "Scooby Dooby Doo!" Yes, a marijuana reference in every single episode of the show."
The first episode of Count Duckula was titled "No Sax Please, We're Egyptian" has the characters singing the "Drunken Sailor" sea shanty. They stop before getting to any of the off-color verses, but suffice it to say, this is not a children's song.
The episode title itself refers to a play in London called "No Sex Please, We're British."
Duck Dodgers in the 24½th Century features an episode called "K-9 Kaddy" co-starring the Goofy Gophers. They tickle-torture K-9 then begin tickling each other and run offscreen. They return sighing and exclaiming, "Oh! I couldn't tell you the last time I had so much fun with a feather!"
Being based on a Troma film, Toxic Crusaders, a kids version of The Toxic Avenger, had this in spades. One notable example in the episode "Toxie Ties The Knot" had a female alien bug character being kidnapped by the Mayor of Tromaville. Thinking that someone is throwing her a bachelorette party, when the Mayor shows up in a bug costume the female alien asks "Are you the stripper?".
In the Talkartoons short Any Rags, during Bimbo's junk auction, we see KoKo the Clown acting very feminine, which makes Bimbo say "Sold to the man in the red bowtie!" (In case you don't know, red ties were a sort of identification for homosexuals back in the day).
The short Minding the Baby has a gag where Bimbo explains why he has to watch his baby brother.
Rachel: Oh, I know I should just ignore her. But Lydia is such a— Kirsty: CARROT! Rachel: ...I had another word in mind.
Kenny of South Park all but exists for this purpose. Kenny's muffled speech due to the parka he wears allows the writers to slip in swear words that keen eared viewers can hear if they listen closely enough that would otherwise be BLEEPed for anyone else.
In the comic series Cyber Six was based on, Von Reichter was a member of the SS. Of course this isn't mentioned in the animated series, but they got away with having Jose (his cloned "son") goose-step from place to place and wear Hitler Youth clothing.
The episode My Two Bobs of Reboot features a game titled "Pantsu Hebi X". Translate it directly and you get "Panty Snake X". Um...
Avengers: Earth's Mightiest Heroes featured several such instances of this - most notably Hawkeye calling the Masters of Evil "tools," and some of Tony's more blatant come-ons.
Ewoks: Characters often say "k'vark" in place where humans would use a four-letter word. And in the second season episode Bringing Up Norky, Teebo says He sure is a pain in the..., but Latara finishes his sentence with Mud puddle!.
PhineasAndFerb: The episode "What a Croc!" has a literal case of this. After Crikey the Croc is rescued and returned to a Wildlife Preserve in the city, Candace tries to take Irving's digital scrapbook tug-of-war style, which results in it flying into Crikey's mouth and getting eaten. Fortunately, Irving's brother has a backup, and all they have to do is wait a few hours note for his brother to get there with the backup. Unfortunately, Candace cuts him off, grossly misinterpreting his meaning, and it takes Irving a few seconds to realize his poor wording. (i.e. What eventually happens to something that's been eaten? ;) )