These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Acceptable Targets: Nick. Nolte. They do NOT let off him and his rather colored past for a moment, and any given riff made in the last year has about a sixty percent chance of including at least one Nolte gag.
Furries (and Bronies as of late).
Rip Torn's alcoholism.
Rosie O'Donnell is another, such as this gem from The Dark Knight, after Loeb drinks acid.
Mike: (as Commissioner Loeb) I just thought of Rosie O'Donnell. (vomits blood)
They are also prone to mocking Bud American Ale, Baconators, the movie Firewall, the show According To Jim, Shia Labeouf, and the driving skills of Kelsey Grammer.
Expect there to be at least one The Room reference once per riff.
It's tapered off of late, but older Rifftrax would invariably fire off a shot at Phil Spector.
(Dozens of small monkeys crawl over Spalko in a speeding jeep)
Bill: This is what Neil Gaiman feels like at Comic-Con.
On a (very slightly) more serious note, the trio has an evident contempt for bigotry either on-screen (i.e. the various examples of Uncle Tomfoolery they see on a semi-regular basis, or the jawdropping misogyny on display in the Wicker Man remake) or off-screen (they lash out a few times at Anita Bryant for her homophobia during the short she narrated) which usually results in them making jokes or comments noticeably more insulting towards the offending party.
They also have carried over their contempt for Woody Allen from the MST3K days, and if anything have become even more venomous. Epitomized by this quip from the Return of the King riff.
Bill: (Just after Shelob introduces herself) Think if Woody Allen was here, he'd say "theres a spider the size of a Buick in this cave"........aaand then he would take nude pictures of his daughter, applaud Roman Polanski's child rape, and call for an Obama dictatorship.
Kevin: (chuckling sarcastically) ah that Woody.
Big Lipped Alligator Moment: The combined "Why Doesn't Cathy Eat Breakfast?"/"Petaluma Chickens" short. The first part never answers the question, and the second part provides no context for what the hell is going on (as related by an impression of Foghorn Leghorn at the end).
There was also this weird-as-fuck audio report of the ridiculous notion that Harry Potter was "Satanic". It was after their Prisoner Of Azkaban riff finished, while the credits were rolling up. Towards the end, while a religious preacher was proclaiming about sinning and cleansing/purging, you could hear a woman screaming all throughout that speech. Three words: What thefuck?
The Order of the Phoenix riff had a similar, but less nightmare fuel filled ending with an audio of an interview with a rather insane preacher about how evil Harry Potter is.
In the riff of High School Musical, Kevin mishears a lyric in one of the songs which leads him to excitedly assume the characters are serving free bacon. When no bacon appears, you hear stock sound effects of gunfire and people screaming, while Kevin maniacally rambles on about wanting his bacon.
During the Harry Potter and the Order of the Phoenix riff, the guys latched onto an obscure Victorian English anti-welsh rhyme "Taffy was a Welshman" for some unknowable reason to the point where Disembodio recited the entire rhyme during the credits.
— *During one of Dumbledore's pauses* I think he just died right there.
An entirely accidental case in Swamp of the Ravens is when they riff an autopsy scene in the usual manner....clearly not knowing said scene was an ACTUAL autopsy that was put into the movie, which makes all the riffs rather disturbing.
A mutual example of this between the audience and the riffers occurs in the Christmas Shorts liveshow after a mild joke about the little girl in "A Visit to Santa's Toyshop" is her father's favorite from Kevin draws groans of horror and disgust from the audience, who clearly think he is joking about something else which then draws a highly disturbed rebuke from Mike that the audience would think this.
Ear Worm: The "Quality, Freshness, and Flavor" song in Three Magic Words, which is compared to "It's A Small World" on the site for its horrible ability to get stuck in one's head.
Genius Bonus: There are a handful of surprisingly high-brow references and jokes in each riff.
"Welcome to Mandelbrot Station."
"There may be a test tomorrow, there may not be." "Ah! Schrödinger's Pop Quiz!"
"Uh, yeah, this Joseph Campbell crap's really derivative, you got any Carl Jung?"
There are a surprisingly large number of tributes to "Howl" and On the Road, especially in the shorts.
In the riff for The Phantom Menace, Jar Jar is called the most embarrassing character since Stepin Fetchit. Unless you're ninety years old or interested in African American cinema history, you probably have no idea what that means.
Though they're hardly the first people to compare Jar Jar to Stepin Fetchit.
In the riff for Revenge of the Sith, Obi-Wan says "So uncivilized" and the riffers say, complete with British accent, "Sometimes I don't think these Coolies deserve the British Raj."
"When a man threatens to poop on the drink cart, take him at his word. Look it up."
Harsher in Hindsight: The commentary for Terminator 3 includes a comment about Heath Ledger getting killed. It was released a little over a year before Ledger's death from a sleeping pill overdose.
A less severe one: in Iron Man Rhodie looks at the War Machine suit and says "Next time, baby," to which the riff is "And Terrance Howard locks in his role in the sequel." The riff was released the very same day that it was announced Howard would be replaced with Don Cheadle.
In the riff of Return of the King, as the camera pans over the ruins of Osgiliath, Kevin quips "The Jersey Shore, present day" as a Take That to the show Jersey Shore. The Rifftrax came out a couple years before Superstorm Sandy laid waste to much of New Jersey's shoreline.
"The death of Phillip Seymour Gaffigan" from Harry Potter and the Deathly Hallows Part 1. Phillip Seymour Hoffman's shocking death would come shortly after its release.
In the Iron Man Riff, while on a little tangent about how Robert Downey Jr. can improve the type of hat he is wearing, they suggest a Sherlock Holmes deerstalker. Cue the announcement for who'll play the detective in the 2009 film...
Also in Iron Man, during the scene where Tony's suit ices up and he tells Jarvis to deploy the flaps, Mike quips: "You said we didn't need flaps, you installed spinning rims instead". Come The Avengers, when Jarvis claims that the new suit isn't ready yet, Tony actually says "Then skip the spinning rims."
During the RiffTrax of Revenge of the Sith, they make fun of Padmé waiting for Anakin in one scene by saying "Mickey Mouse is waiting for him." to which Kevin says as Mickey Mouse "*chuckles* Hi, Anakin! *chuckles again*". Guess who bought Lucasfilm and is making Star Wars Episode VII?
During the riffing of Daredevil, Mike continues Matt Murdock's (Ben Affleck) narration by stating that he would become a hero called Batman until a rich kid from Gotham sued him for the copyright. Well, guess who is playing the rich kid from Gotham in the Superman sequel.
During the climax of Dr. Who and the Daleks, Kevin jokes about how the Daleks are made to shoot each other. ("You shot me! You knew it was me, Carl! You looked me in the eye!") That was funny enough. Then, it got funnier when what the Doctor really did to the Dalek fleet around Gallifrey was revealed in "The Day of the Doctor".
In the "Revenge of the Sith" riff Bill raises the possibility of three more sequels during the aftermath of Mace Windu's death. 2 years later.....
Some of the pre-show cards for the Starship Troopers live show had movie titles to unscramble. The answer card for one for Monsters University commented "At least it's not Cars 3". Months later, Pixar announces Cars 3.
And for those who were wondering: Yes, corn is a type of grass.
Nightmare Fuel: The sequence in the short "This Is Hormel" of cow carcasses getting skinned by machines audibly horrifies the guys and likely horrifies many in the audience (especially the tail...the horrible tail...) so much so that they make it a running gag for the rest of the short that anyone who pisses the company off is imprisoned within the "Hide Cellar" where this all takes place.
In Swamp of the Ravens there is both a real autopsy used by the movie which passes by unnoticed by the riffers, but also a sequence of dead malformed foetuses pickled in jars (and which one hopes to god are not also real) which the guys find utterly horrific.
And of course there is the Ice Cream Bunny.....
The above stinger for the second Harry Potter riff also counts due to how fucked up it is.
They are also rather peturbed by the surprisingly dark and brutal ending of Zindy the Swamp Boy where the titular child is literally slaughtered by a wildcat, though they still play it for Black Comedy.
Mike: This has been "Zindy the Swamp Boy" dies alone and afraid with no loved ones around after getting eaten by a jungle-cat.
After the graphic birth scene in Twilight Breaking Dawn Part 1, Mike recounts how it's more beautiful than the time he and his brother threw a live chicken into the pig pen and watched the pigs rip the chicken apart and eat it alive while it screamed like a woman. Bill sounds honestly freaked out as he quietly begs Mike to say he made up that story.
Padding: The guys are pretty merciless about pointing this out in movies. This is especially true in their Video On Demand movies, as those tend to be the kind of low budget B-movies that make frequent and painfully obvious use of padding.
Kevin: (during a scene of a police car pulling up to a house in The Curse Of Bigfoot) No detail is left out...in our goal of padding this super-thin plot out to feature length.
Throw the Dog a Bone: Occasionally they will show some genuine affection for even the worst films they watch, usually for certain characters (Palpatine, the Volturi) or certain scenes (Picard mourning his brother and nephew's death).
We're Still Relevant, Dammit: Occasionally some of their pop-culture references can come across as this, but its only really noticeable if they are just shouted out references to current pop culture without elaboration or referencing memes, furry/brony jokes included.
On the other hand, they'll sometimes make jokes that refer to pop culture from about 40 years ago, and then laugh sadly about how old they are.