Is Barney a selfish and contemptible Jerkass who deserves what happens to him (i.e. being temporarily abandoned by Ted for sleeping with Robin, and getting banned from laser tag for assaulting children)? Or are his actions justified based on his crappy childhood and rejections, among other issues that make him fragile? His shrink thinks so, calling him "A narcissist with severe attachment disorder"
When Future!Ted revealed all the amazing things Robin did over the years to his children, was it to fill the void of not having kids or did she really want to do them? And with the twist ending that he's still in love with Robin, was it just a way to boost her so that the kids would be okay with them dating?
Any character can be subject to this given that the whole story is being told from Ted's memories of events that happened twenty years ago and he may not be remembering things perfectly or embellishing the narrative a bit to make himself look better.
The series as a whole evolved into this. Before the Mother was revealed in Season 8, there had only been minutes' worth of hints about her.
The Ted/Robin/Barney love triangle.
In the Season 6 premier, Ted and Marshall are at a wedding. The groom is revealed as Barney a season later and Robin as the bride a season after that. It takes another season for Barney to propose and another for the wedding to conclude.
Award Snub: As of 2010, Neil Patrick Harris has been nominated for four Emmys for HIMYM, but has lost all four times (to Jeremy Piven, Jon Cryer and Eric Stonestreet). However, Harris won two Emmys in 2010 for guest starring on Glee and hosting the 2009 Tonys.
Base Breaker: From the evidence on message boards, it seems that if you watch the show, you either love Lily and think she's a hilarious and endearing character and wonderful wife, or think she's a mean, shallow, selfish bitch who doesn't deserve Marshall. The latter is probably a vocal minority, but the split is quite noticeable.
Stella. She became The Scrappy after "Shelter Island." About half the fanbase thinks "As Fast As She Can" redeemed her; the other half thinks it made her even WORSE.
Ted has a split similar to Lily's, but there's a notable trend for his haters to be extreme Barney fans. Given the fact that Ted and Lily are far less willing than Robin and Marshall to ignore Barney's bad behavior, it's hard to stop certain suspicions from emerging...
Big Lipped Alligator Moment: Barney and Robin's dance in the seventh season premiere. Very sudden, very elaborate and the rest of the reception joins in, and then completely ignored the second the song ends.
Crazy Awesome: Barney, apparently. During a joyful "you said I was crazy!" speech, he mentions that even his psychiatrist thinks he's crazy, then names the diagnosis: "narcissist with severe attachment disorder".
Zoey in season six. Even Marshall's brother and mom get seriously invested in the idea of Ted and Zoey dating, though that is somewhat justified in they had never met her and just know her as "the girl Ted likes."
The episode when Ted Mosby flies his mom and dad in. It's mentioned that they don't really talk about their problems. Barney sees Mr. Mosby making out with another woman in the bar, and tells Ted. When Ted confronts him, Ted's parents reveal they've been divorced for nine months (and separated for two years) and simply chose not to tell Ted. During the credits, Ted asks how Grandma is; she hasn't been returning his calls. His parents look uncomfortable.
Anything involving Barney and the women he sleeps with.
In Sorry, Bro when Lily finds out Ted is getting back together (again) with the pretentious, cheating beeyotch he dated in college: "Ted, honey, go outside and bite the curb, I'll be out in a minute..." Hahaha, oh, Lily- wait...
"Bang, bang, bangity-bang, I said a bang-bang bangity bang!"
When A.C. Newman's "Prophets" plays at the very end of The Leap as each character takes a leap of faith into a new year, it is so awesome that it almost makes you want to jump off a New York City rooftop yourself. But don't.
Also in the episode The Leap, the music playing during the fight with the goat is the song "Murder Train" from the Sandcastles in the Sand episode (played by Robin's ex's band). They get a lot of mileage out of that song, it's also in the reveal of Marshall's fight club with his brothers, the big fight Robin and Barney have in season 5, and pretty much any other time they need a metal track.
A certain scene concerning Ted's career was appropriately accompanied by The Decemberists' "Here I Dreamt I was an Architect"
Parodied in The Limo where Barney's mix tape is "all rise" in order to "get psyched". As it keeps being restarted we only ever hear the first track, Bon Jovi's You Give Love A Bad Name, although the full track list is available on his blog. The song is then used as a straight example near the end of the episode.
Deee-Lite's "Groove Is in the Heart" during the bizarre Barney/Robin dance scene.
Designated Protagonist Syndrome: Ted is seen by certain fans as rather dull in comparison to his more interesting friends. This isn't helped by the fact writers have had his character constantly going through the same motions of falling for a hot girl, making an overblown romantic speech and then predictably breaking up with her, for the last six seasons.
Designated Villain: Barney in "The Goat". Put aside The Bro Code, Barney did absolutely nothing wrong, because Robin has been single for a year after she broke up with Ted; she is fully aware of her action with Barney, but nevertheless we're forced to believe that Ted is right for cutting his friendship with Barney and Barney's guilty for giving comfort to Robin when she needs it. It also didn't help that Robin's explanation to Ted made it sounds like Barney is taking advantage of her fragile condition to have sex with her, Marshall and Lily are not helping either with neither of them even bothering to doubt Ted's rash decision despite Barney being basically the reason that they're back together in the first place.
Drinking Game: In the DVD commentary for the pilot, Neil Patrick Harris suggests one where viewers drink every time his character drinks following a punch line. Show creator Craig Thomas follows by suggesting a drink every time a characters says "awesome," but joked that it may actually cause alcohol poisoning.
Do not mention "The Rough Patch" around Barney/Robin fans.
And definitely don't mention the finale around them. Though most people are open to counting the alternate ending as canon.
Fetish Retardant: Post break-up with Don Robin. As Barney puts it "you're giving me a de-rection". It should not be possible to uglify Cobie Smulders that much.
Growing the Beard: Generally considered to be "Slap Bet," although other popular choices are "Drumroll, Please" and "The Pinneaple Incident", the latter of which was the first episode in the series to use Anachronic Order.
A season 1 episode has Barney courting a bridesmaid, his excuse for never seeing her again being that in the morning he's shipping out with the Peace Corps for two years. We find out mere episodes later that his Start of Darkness was getting stood up by his girlfriend the day they were supposed to ship out with the Peace Corps together for two years.
Immediately before his first date with Stella, Ted acknowledges--for probability's sake--that the relationship will probably end on a bad note.
Several times during the first few season, Robin talks about she doesn't want kids. In season seven, we learn she can't have kids.
Later, in a season three episode, we learned that 'Aunt' Robin appeared prominently in the pictures drawn by Ted's kids.
Not that watching a gay man play straight is hilarious, but much like his role in the Harold and Kumar series, the extreme degree to which Neil Patrick Harris's character womanizes was cast in a humorous, ironic light after the actor announced his homosexuality.
Ho Yay: "Three Day Rule" is packed with this. There was the fantasy of Marshall and Barney cuddling together in cheerleading outfits, Marshall and Barney on the brink of sexting Ted while pretending to be a girl he likes, and later competing over who Ted would rather sleep with. Not to mention the Ho Yay generator Stan, who has such a good grasp of romantic language that Barney and Marshall nearly fall for him.
Barney: Why do we keep trying to have sex with Ted?//
Marshall: I don't know, it's weird.
The first episode has Marshall (fake)-proposing to Ted. And it also has Barney kissing Marshall.
It's also canon that Lily has sexual dreams about Robin and they kissed after Lily laments never having a "lesbian experience".
Lily full stop with Robin. The last episode (The Broath) has Lily mention that she tried (and is upset that Barney refused) to get them to have a threesome with Robin. When Barney says Lily and Robin have to kiss Lily is all for it, then gets carried away and ravishes her.
"Rebound Bro" has Barney and Ted acting as if they've broken up as a couple.
Barney in "Unfinished" in season 6 tries to seduce Ted into taking an architect job at Goliath using his techniques to pick up women. Which would lead to this gem (and gets lampshaded by Lily later)
Ted: Barney wants me to take the job so bad he's putting the moves on me?
In the episode "Slap Bet," after Barney tells Marshall that his hand is 'monstrous,' Marshall replies "What did you expect? You've seen my penis."
This extension of a scene in Season 3's "Third Wheel". (@ 3:26)
Barney's Relationship Advice speech to Marshall in "Bagpipes" starts with Barney talking over Marshall's shoulder, and ends with Barney's tongue practically in Marshall's ear while Marshall's eyes are almost completely glazed over. With a running theme in the episode about how hypnotically powerful this speech is to Marshall.
Ted and Barney's fantasy Super Date, complete with a musical number in "Of Course" has both of them so flustered by the end of it that they both shake it off by going to a strip club.
In "The Mermaid Theory", when pirate!Marshall starts to see cabinboy!Barney as a mermaid:
Marshall: Dude... We need to find land...
Marshall even has this with a random male at the collage he went to with Lilly and Ted: "Sweet and Cute but Just enough of a Jerk so you want to change him"
Marshall and Brad, when Brad was dumped by his bride.
In "The perfect week", Ted slaps Barney's ass reassuringly before he goes to pick up a girl.
Hollywood Homely: Post-breakup Robin. All they've done is put Cobie Smulders in sweat pants and messed up her hair. One shower later and she's fine.
Robin needs to shave her legs, so after the guy invites her back to his place, she ducks into the restaurant bathroom where there is guaranteed to be no shaving cream rather than go back to his place where there is guaranteed to be shaving cream. It doesn't help that from what we can see, her legs don't actually seem that hairy.
Marshall quitting his job without having another job. He's 30-ish with a mortgage and law school debt.
Lampshaded in the show how everyone pretty much grabbed the Idiot Ball when Marshall and Lily bought the apartment, despite massive credit card debt. They never even checked out the apartment fully to realize it was near a sewage plant and had a crooked floor.
Idiot Plot: Played for Laughs in Marshall and Lily's wedding episode. Needing to cover up Marshall's ruined haircut, the guys scramble for ideas but never thought of simply getting a hat.
Informed Wrongness: Ted is treated as an ignorant jerk for still seeing Heather as an irresponsible teenager. This is despite the fact that she really does have a very long history of being irresponsible. And the way she decides to prove Ted wrong is to have Barney and herself undressed in his office, get caught by Lily, and then accuse Ted of being a jerk for making the obvious assumption that they had sex. Yeah, way to prove you're a smart, mature adult Heather.
Marshall: Deep in the Amazon rainforest, there is a tree that only grows around the body of an existing tree. It cannot survive without this tree; it's supported by this tree. Lily, we are that tree...we grew around Ted and without him we're slowly dying!
One might even speculate that part of the reason Ted's romances keep failing is because he's entangled in two OT 3's and can't focus on a person from outside of his group. He even explicitly declares that he will never get serious with a woman who doesn't like his friends.
They also did one with Barney and Robin... in the episode they actually hooked up. The tease allowed the actual hookup to be a surprise.
Snark Bait: The utter failure of the show to hide Cobie Smulders' pregnancy. In fairness, Cobie was utterly massive at that point and even a Hollywood movie would have had trouble hiding it but it's still hard to miss.
At the end of the first season, Lily breaks off her engagement with Marshall and leaves for San Francisco, leaving him crushed and sitting outside the apartment in the rain holding the engagement ring.
The ending of "Benefits", when Barney blurts out to Robin that he's in love with her...and she assumes he's making fun of Ted's overly-emotional nature. She then goes on to say (regarding her and Ted) that dating friends never works out. Barney looks completely heartbroken.
The ending of "Cleaning House", which uses a montage set to "Stand By Me" to show that Loretta was actually a wonderful mother.
In "Bad News": The death of Marshal's dad. It happens off-camera, but Lily having to deliver the news to Marshall is heartbreaking.
Even more so in the following episode: when Marshall thinks the last call his dad ever made to him was a pocket dial. Marshall's rant to his friends, his wife - even God - about how unfair his dad's death is...it's got this dead-inside troper tearing up. Jason Segel DESERVES an Emmy nomination; he can really act.
This troper teared up the moment you see Marshall's dad's phone ringing on his work bench, with him no-where in sight. You just know that if he isn't there to answer Marshall's call, then something has happened to him.
Barney and his dad, Jerry's talk in "Legendaddy"
Barney:You're lame. Okay? You're just some lame suburban dad!"
Jerry: Why does it make you so mad?
Barney:Because if you're gonna be some lame suburban dad, why couldn't you have been that for me?
Later in the same episode
Barney: A kid needs a hoop...
The last scene in A Change Of Heart, where we see Barney enter the restaurant and meet Nora's parents, then it cuts back to him standing outside the restaurant, revealing it to be his imagination. The look on his face as he decides not to go in is heart-wrenching... Wow, Season 6 is pretty sad.
The ending of Tick, Tick, Tick... poor Barney, he did the right thing, and ended up alone...excuse me, I need a tissue.
Especially the scene where Ted walks into his apartment and sees Barney removing rose petals from Robin's bed and blowing out candles. It was the most vulnerable, romantic thing he's ever done, and his heart was yet again broken for the umpteenth time. One wonders how he'll pull himself back after this...
To make matters worse, poor Nora gets caught up in all of this despite doing nothing wrong. After taking a huge chance on Barney, she has to find out that he cheated right after he meets her parents.
Symphony of Illumination. The episode starts with Robin talking to her kids about how she met their father. Robin learns she isn't pregnant with Barney's children, then learns she can't have children at all. At the end, you learn the two kids she was talking to were imaginary. Good lord this show.
Tethercat Principle: In Karma, Patrice is still sitting there, excitedly waiting for Robin to arrive...
Uncanny Valley: In the season six episode "Baby Talk" Marshall imagines his daughter marrying Barney who appears to have maintained his good looks by a permanent botox. His face appears to be made of plastic, and it does not move at all. Take a look.
The Untwist: The reveal of Robin as the bride at Barney's future wedding at the end of Season 7 came as an utter shock to about 2% of viewers. At most.
Values Dissonance: The show ran into huge problems with this. It ran from 2005 to 2013 living through society's divorce from the Dogged Nice Guy and Opposites Attract, causing many to take more critical looks at the show's earlier seasons even as it still aired. And then there was the finale which was written in 2006 and by god was that felt by a 2013 audience.
Warped Aesop: Lily, after Marshall's co-worker Jenkins drunkenly kisses Marshall, her immediate reaction is to go to Lily, take full responsibility for what happened, and apologize like a reasonable adult. Lily's reaction is to beat the crap out of Jenkins while Barney takes pictures. The only moral here? The Aldrin-Ericksons are nuts.