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.
YMMV: Regular Show
Alternative Character Interpretation: In "House Rules" Mordecai learns that Rigby may die young or just leave Mordecai. Have episodes like "Think Positive", "Best Burgers in the World" and "Replaced" made him more lazy in order to hang out more with Rigby?
Arc Fatigue: The development of Mordecai and Margaret's relationship has been agonizingly slow. After four seasons of Mordecai making minimal effort to take their relationship beyond friendship, Margaret finally gives him a kiss when he sees her off at the airport. So they're finally together, right? Nope, next episode involving them says that Mordecai is still considered to be in the "friend zone". At the end, they share a mutual kiss, and the next episode has Margaret introducing him to the rest of her family. But "Steak Me Amadeus"'s plot revolves around Mordecai asking Maragret to be his girlfriend. Given everything that had happened prior, it was pretty easy to think that she already was.
Margaret is either a funny, well written supporting character or an annoying, bland plot device for Mordecai.
Thomas, the new employee is either an okay addition to the cast or he's The Generic Guy with no mention whatsoever how he got the job or why the park needs an intern (though in "Exit 9B," it is implied that he is there for college credit).
Big Lipped Alligator Moment: Averted. Weird stuff does go down on the show, but, unlike most Big Lipped Alligator Moments, the weirdness is part of the plot.
Crazy Awesome: The first two-thirds of most every episode is pretty straightforward and nothing unusual for most TV shows, but when you come to the last third, you'll have a hard time picking up your jaw.
Designated Protagonist Syndrome: Mordecai can fall a bit into this, as most of his plotlines seem to involve getting together with Margaret and being more level-headed than Rigby.
Dude, Not Funny!: Muscle Man laughing as Rigby's choking in "See You There". While the show's usually absurd enough in its use of death as a punchline, that particular moment was a little too serious.
How many fans reacted to the ending of "The Best Burger In The World" where the food truck falls in a ditch and Mordecai and Rigby lose out on getting their burgers (more specifically: Benson ate them purposely.)
Rigby's entire behavior towards Mordecai in the episode "Do Me a Solid".
What most people consider of the ending to "Do or Diaper", where at the exact moment Margaret is about to kiss Mordecai she deliberately misses so that way he will lose the bet and have to wear a diaper for a whole week.
Quips' jokes from the episode with his name. Some of his jokes are genuinely lame unfunny jokes that he is actually funny. However others, especially those directed at people, seem so unsympathetically cruel that they cross from being Innocently Insensitive to being just plain insensitive. Pops and the Guardian of Youth insulted by Quips could attest to this.
"A bunch of baby ducks, send them to the moon. A soda machine that doesn't work, send it to the moon."
"GIVE US A RAISE, LOSERS!"
Canon example: "Summer Time luh-huh-huvin', gonna head down to the beach and do some beachy things!"
"Awww snap! Awww snap! come to our macaroni party and we'll take a nap!"
These two songs battled each other with actual rock star avatars, making it a Crowning Moment Of Earworm.
Ra-ha ringtone, pick up your phone!
BECAUSE WE KNOW EVERYTHING ABOUT SCARY MOVIES AND YOU KNOW NOTHING ABOUT SCARY MOVIES.
Too many to count from "Silver Dude".
Ensemble Darkhorse: The baby ducks became quite popular over the course of their two appearances.
Genius Bonus: The Dudetime Cologne attracts unicorns. In medieval times, it was believed that a virgin's purity would attract unicorns. Therefore, guys who use Dudetime are virgins (and so is Mordecai).
Growing the Beard: First season's episodes are pretty formulaic: Rigby and Mordecai plot a Zany Scheme, it backfires horribly, nothing is achieved, they end in deep S, bonus points for Skips saving the day and/or Benson getting pissed off at the very end. Second season's episodes usually make it so the positive outcome is roughly equal to or outweighs negative, but we don't know the way in which both come, making plots much less predictable. Also, the show's pretense of being a "kids' show" is hanging by a thread moreso now than it did when it started.
Harsher in Hindsight: The "Viral Video" episode which has a Warden trying to police the web. SOPA almost did that in 2012 (thank goodness it was vetoed).
They're doing it again with CISPA, and unfortunately, that actually passed — until the Senate put its foot down and decided NOT to vote for it at all after stalling.
Ho Yay: While the show generally manages to avoid this by having Moreecai and Rigby hardly have any affecionate moments, it still shows up. For example:
Relationship Writing Fumble: The 'will they or won't they' attitude of the Mordecai/Margaret ship. In "Picking Up Margaret," it was leaning towards, "They will," but "Steak Me Amadeus" established that Margaret will never be Mordecai's girlfriend because she got accepted into her dream school.
"Video Game Wizard" features a knockoff of Rush's "Subdivisions" on the car-ride to the tournament.
"Steak Me Amadeus" has one for Lynyrd Skynyrd's "Tuesday's Gone" after Mordecai gets dumped.
Take That, Scrappy!: Muscle Man's failed attempt at standup in "Under The Hood": he makes a 'my mom' joke. No one in the crowd laughs and some even get hostile towards him, to the point where he has to leave the stage. This is exactly the reaction a lot of viewers have to him and his jokes.
Also "Rage Against the TV" in which he gets knocked out by The Hammer.
Benson gets another one from Mother Duck who points out Mordecai and Rigby saved the park AND the world despite the damage. That Benson yelling at babies is just plain wrong. AND that he was the person who ordered Mordecai and Rigby to stop the Geese in the first place.
Tastes Like Diabetes: Don asking for hugs, amplified by the fact that he asks by saying "Give me some sugar!"note Though possibly it's more he's kept a childlike view of showing affection, as "sugar" is the slang some very young children use for hugs and kisses. Note the use in the flashbacks. He even starts by hugging Benson and Pops who are made of sugar.
Also note, we're not entirely sure how old Don is. Rigby is 23 and he's the older brother, Don apparently just grew rapidly and everyone thinks he's older than he really is, which Rigby actually says. So it makes since he's more childlike than Rigby.
They Wasted a Perfectly Good Plot: "Bad Kiss" pretty much wastes the chance for Margaret and Mordecai's relationship to finally go further than friendship, thanks to Mordecai chickening out on kissing her. He actually DOES get a kiss from her in "Picking Up Margaret.
What Do You Mean, It's for Kids?: More sex jokes, frequent lethal use of weapons and mild profanities ("crap", "sucks", even "pissed") then you can shake a yardstick at. Justified, as Regular Show is based on two short films J.G. Quintel made in animation school called "2 in the AM-PM" and "The Naive Man from Lolliland." While "The Naive Man from Lolliland" is safe for family viewing (the one use of the word "hell" wouldn't phase most viewers), "2 in the AM-PM" isn't — at least by Cartoon Network's already selective standards.
The Woobie: Thomas who debuted in the episode "Exit 9B" is most likely one of these. He was in the right place at the wrong time and witnessed all the parks employees (except Mordecai and Rigby) get brainwashed and was forced into being the lackey of the main villain of the episode. The villain was also downright verbally abusive to the poor goat.