In the glittering, high-stakes world of Manhattan's Upper East Side, the bond between Serena van der Woodsen, the effortlessly radiant "It girl," and Blair Waldorf, the fiercely ambitious and impeccably styled queen bee, formed the core of harsh reality of rewatching Gossip Girl all these years later.

Serena, with her spontaneous spirit and magnetism, often inadvertently found herself in the spotlight, a dynamic that frequently stirred Blair's underlying insecurities and yearning for recognition. Blair, in turn, possessed a sharp wit and determination, yet her vulnerabilities often led to confrontations, particularly when she perceived slights or betrayals. Serena and Blair's enmeshed lives often erupted into conflict in some of the Blair and Chuck's worst moments.

9 Arguing About Blair’s Feelings For Dan

Season 5, Episode 16, “Cross Rhodes”

Gossip Girl’s plotlines thrive on misunderstandings and witnessing moments out of context, which is exactly what transpires in “Cross Rhodes”. The scenario begins with Blair and Serena arguing about Blair’s true feelings for Dan, which she vehemently denies. This fight is more on the playful side, and it conveys that for all their faults, B and S know each other inside out, and their patterns are still repeating themselves five seasons in.

Serena accuses Blair of running away from her feelings and ignoring them, which is hilariously rich considering Serena famously always “has to go”. Blair’s response is to prove to Serena that she only likes Dan platonically by spending the day with him, and goes to keep him company at a play rehearsal. Ultimately, Serena is proven right and walks by just as Dan and Blair are kissing, leading to another argument and Serena scolding Blair for not being honest, either with her or with herself.

8 The Photoshoot Argument

Season 1, Episode 4, “Bad News Blair”

This season 1 argument between Serena and Blair establishes early on in the iconic 2000s series that even when the pair are on good , it is usually on shaky ground. The situation starts out with Serena ing Blair while she models for her mother’ Eleanor Waldorf's clothing line. At first, it is heartwarming, with Serena giving Blair tips on how to loosen up, as she can see the photographer feels Blair is too prim and proper. This inevitably leads to Serena’s natural charm outshining Blair.

It is a recurring source of insecurity for Blair that Serena gets positive attention so effortlessly.

This scenario is especially difficult for Blair because she and Eleanor already have a strained relationship, so to see her seemingly favoring Serena is a huge blow to her self-esteem. While it is not necessarily Serena’s fault, it is a recurring source of insecurity for Blair that Serena gets positive attention so effortlessly. In the argument, this insecurity pours out when she declares, “You take everything from me [...] You can’t even help it, it’s just who you are.” Her acknowledgment that it is not even intentional on Serena’s part shows that she is self-aware of her jealousy.

7 Blair Freezing Serena Out

Season 1, Episode 1, “Pilot”

Season 1 of Gossip Girl does a really good job of establishing Blair and Serena’s contentious friendship and why all is not well when Serena breezes back to the Upper East Side after disappearing for several months without a goodbye. What you see is what you get with true Gossip Girl protagonist Blair, and she tells Serena her perspective in no uncertain during their face-off on the Met steps in the show’s pilot. She is clearly freezing Serena out, and she tells her why — “Until 12 hours ago, everyone thought you were at boarding school.”

Within a few episodes, the show establishes the extent of Blair’s hurt that Serena disappeared abruptly without a word, leaving her feeling isolated with difficult family and relationship problems. This sets the tone that while Blair is forthright more often than not, there are also unseen depths to her insecurity that unfold throughout the show. Even in this early scene, her catty comments only thinly mask the simmering resentment that comes from a wounded place. Not to mention, the outfits of Blair and her minions set the preppy tone for the fashion in the time-capsule series.

6 Blair Kicks Serena Out

Season 5, Episode 24, “The Return of the Ring”

Blair went for scorched earth here, ultimately kicking Serena out of her penthouse. Both characters have given as good as they got in the episode. Previously, it was revealed that Gossip Girl’s titular stalker had excerpts of Blair’s diary courtesy of Serena. Although Serena had the excerpts in her possession merely to know she could leak them if she wanted to, it was Dan as Gossip Girl who leaked the diary - but at this point, Serena is to blame.

In retaliation, Blair sabotages Serena’s job opportunity, which she protests meant a lot to her. Serena, in turn, sabotages Blair’s relationship with Chuck. Both clearly have their faults in the scene that they astutely point out — Dan is equally responsible for what transpired between him and Blair, so she didn’t “take” Dan, but equally, Blair does cheat on multiple boyfriends to be with Chuck without itting she is in love with him. This is the hard truth Serena fires at Blair, and this is what gets her kicked out — she really "had to go" this time.

Particularly in the context of Blair’s diary drama, this is painful...

However, it is what she says next that is really below the belt. She tells Serena, “The best time I ever had was when you were gone six years ago.” Particularly in the context of Blair’s diary drama, this is painful because of another personal writing in season 1. A letter Blair reads to Serena that she never sent earlier in the show details how lonely she is without her and how upset she was that she left, making this later contradiction particularly brutal.

5 Blair Pushes Serena Into A Fountain

Season 4, Episode 1, “Belles de Jour”

The fight in “Belles de Jour” is one of the pettiest on Blair’s part, but also one of the most entertaining. After Serena is accepted into Columbia, Blair is trying to persuade her not to go, as she is attending the same university. Blair wants a fresh start, which surely Serena can understand — but, to be fair, Blair has no right to tell her friend where she can or cannot go to school.

After Serena suggests they simply enjoy their double date with the Prince, one of Gossip Girl, Blair selfishly decides she wants both men to herself for the evening, and she pushes Serena into a fountain. After the hilarious cake scene of season 3, it’s almost like a pattern was emerging.

4 Serena Pushes Blair Into A Cake

Season 3, Episode 8, “The Grandfather: Part II”

This argument is one of many times Serena and Blair’s friendship was toxic in Gossip Girl. Blair brings someone she just met to Chuck’s party and flexes to Serena about how politically well-connected she is and that this woman is her “best friend”. They continue to argue back and forth throughout the evening, with Blair bringing up old wounds about having to clean up Serena’s mess, referring to her past. This culminates in an argument threatening the atmosphere of Chuck’s “classy” event which they are, according to Chuck, turning into more of a “sample sale at an outlet mall”.

Blair goes for the low blow once again...

When it is revealed that Blair’s new friend is an escort, Blair goes for the low blow once again, telling Serena, “The only prostitute here is you.” She then tells Chuck she wants some cake, before Serena pushes Blair’s face into the red, white and blue dessert. The best fights are when they come to a head dramatically like this, and Blair certainly had it coming with her hurtful comments throughout the night. What perhaps puts the icing on the cake (pun intended) is that Blair licks her lips after her faceplant, showing she really did want some cake. At least it was tasty.

3 The Fake Fight

Season 4, Episode 3 “The Undergraduates”

This “fight” between Serena and Blair is so fun to watch precisely because another character has tried to pit them against each other, and they turn that on its head. Just when the viewer thinks you can always count on S and B to feud and it’s a repetitive device, they team up to have a scheme of their own — it’s a great piece of writing, and also shows that their long shared history wins out in the end.

The scene starts out with a real relic of the 2000s, with Gossip Girl's forgotten Juliet asking a group of girls, “What’s going on? A flash sale on wrap dresses?” before they reveal Gossip Girl is streaming a fight between Serena and Blair regarding the supposed sabotage of Serena’s college plans. Juliet plugs what she thinks is the result of her scheme into several screens. In their fake argument, S and B seem like a parody of themselves, ranting about each other’s dating history before Blair says something below the belt, and they resort to hair grabbing.

When Juliet goes to the source of the scene, she is met by the pair of them sitting calmly and waiting for her, enhanced even further by Dorota hilariously offering her champagne. The scene is brilliant because not only is the viewer rooting for Juliet to get her comeuppance, but Gossip Girl subverts its own tropes for a pleasant surprise.

2 The Field Hockey Fight

Season 1, Episode 3, “Poison Ivy”

One of the most unforgettable conflicts between Blair and Serena is the early-season fight in “Poison Ivy”. Like the apt episode title, the pair certainly irritate each other — in the episode prior, Blair found out what happened between Serena and Nate before she abruptly left for several months. Blair sets the tone for this episode when Serena arrives late for an assembly about Brown University, and Blair quips, “Brown doesn't offer degrees in sl*t.”

This signature pettiness escalates with the two being at each other’s throats, especially in a violent field hockey scene. In a strange way, it is refreshing to see them have it out straightforwardly like this - after all, Regina George of Mean Girls was prescribed lacrosse as an outlet for her aggression. Their behavior in the scene brings out their key traits, with Serena wanting to call a “truce” before Blair has had much opportunity to vent her valid frustrations, and Blair playing dirty instead by feigning injury.

1 The Yale Fight

Season 2, Episode 6, “New Haven Can Wait”

The Yale fight takes the crown as the most iconic Blair-Serena dust-up in Gossip Girl. It escalates because Blair insults Serena’s intelligence, leading Serena to show up at Yale to get even, rather than visiting Brown like she originally planned to. She brags that she would be stealing Blair’s answer to the Dean’s question, so Blair gets her own back by indirectly bringing up a horrific moment from Serena’s past in public, one of her worst decisions in Gossip Girl.

They take it outside, which leads to arguably the most iconic physical altercation between the two characters — especially when Serena grabs Blair’s frilly headband, saying she really hates it. Whether the viewer is team Serena or team Blair in this episode, both of them are trifling with each other’s futures on the Yale visit and look as bad as each other. Ivy League is everything to these characters, so their brawling on such a dream campus was a definite low point in their Gossip Girl frenemyship.