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In an otherwise chilling and well-acted scene where Viserys is bellowing insanely just before his death, it can end up causing some chuckles if you realise his insistence that he is the dragon is awfully reminiscent of the memetic phrase"Fuck you! I'm a dragon!"
The dogs that play the direwolves are not very good doggy actors. It's very hard not to laugh when a happy puppy jumps on top of a chew toy and gnaws on it with glee as the CGI blood flies everywhere.
My favorite is when Ghost (who is completely silent in the books) is trying to warn Jon Snow that the wights are up and about. The "wolf's" whining and scratching at the door was so dog-like that I half expected Jon to ask, "What is it, girl?Did Rickon fall down the well again??"
YMMV, but the insane level of Fanservice becomes kind of funny after a while. The sheer non-stop boobage crosses over from sexy to hilarious round about the dozenth time naked chicks are just sort of... there... in the scene.
On this note, a Deleted Scene shows handmaiden Doreah strangling Irri to death while reciting "sexy" dialogue about erotic asphyxiation. The logic seems to be that because she's a courtesan, she has to do everything sexily, including cold-blooded murder. It's worth a few eye-rolls.
Indeed, before the DVD came out it was the most anticipated of the four deleted scenes included. After the DVD came out, everyone agreed that it was the worst of the four—if not the whole series—and it was a good decision to leave it out. Most people point out to the absurdity of the monologue, that Doreah's motives to betray Dany are even less evident after watching this scene, and Roxanne McKee's poor acting through it.
Daenerys softly weeping whilst Drogo smashes repeatedly and enthusiastically into her quivering arse whilst doing her doggy-style was definitely a mildly amusing "Oh for God's sake" moment....
Daenerys' bathtub scene in Season 3 deserves a special mention. One can basically imagine the prop department painstakingly adjusting the water-level in the tub until Emilia Clarke's nipples stick out of the bathing water in the intended way.
PLAY WITH HER ARSE!
Drogo's hammy ranting speech about what he'll do to Westeros when he invades to avenge the assassination attempt on Daenerys' life. And then he dies.
In one Fanservice scene, Theon is having sex with Ros. Alfie Allen puts a lot of effort into his Immodest Orgasm... but it looks like he has had twelve-thousands volts put through him from the way he jerks around in ecstasy, and he bites his lower lip, which, combined with his little beard, makes him look like an electrocuted rat.
And since Allen isn't shy at all about doing full frontal himself, we get to see that Theon's penis apparently instantly deflated once he was done. WTF?!
During season two, Littlefinger has a good deal of scenes original to the series. A good idea so far, since he has very little to do in the books at this point. Except, they were so desperate to keep giving him stuff to do that he seems to be teleporting around Westeros at random, at the same time as the show is trying to build up tension about how long it takes to get anywhere.
Also, Littlefinger becomes so increasingly Obviously Evil instead of Affably Evil, and it starts to get ridiculous that anyone could listen to him or he could accomplish anything on the scale he does after awhile.
In fact, apart from the very painfully non-narmish wildfire scene, pretty much all of the battle scenes in the Blackwater episode, with the ridiculous amount of plasticine men-at-arms. This doozy of a quote from The Hound takes the cake though:
Loras Tyrell talking about jewelry and how he dreamed of his wedding day as a little boy. Because apparently the numerous saucy bedroom scenes with other men weren't enough to convince us he's gay.
EVERYTHING about Daario Naharis. The man looks like he fell through a time portal from the set of Xena: Warrior Princess, and his lines sound like something out of bad fanfiction.
This is as good an explanation as any for why he was recast after season three.
And while Michiel Huisman's performance is a good deal less silly, there's still the matter of the number of times Daario's name is said in the season 4 premiere to make sure we know it's the same guy.
In Mysha, a very distraught Ygritte has Jon Snow at arrowpoint. Jon tries to plead his way out and tells her that he needs to go home. He sounds extremely whiny and petulant especially when earlier in the episode, Joffrey shrieks at his grandfather that he is not tired. One of these performances was intentional. The other? Not so much.
Daenerys crowdsurfing in the final scene of season 3. The scene is going great, but then it suddenly turns into a rock concert.
Chaosh isn't a pit... Chaosh ish a LADDAH.
Littlefinger's accent in this episode and onward. It's really had to take all his Magnificent Bastard scheming seriously when he's pretending to be Irish Batman.
Rose Leslie's accent as Ygritte starts to verge on the narmy after a while in Series 3, and evokes the kind of stereotypically gobby northern bint encountered on a night out in Wigan, as opposed to a hardened warrior woman from beyond the wall — "I'm Jyon Snuuuuur — raaaaght fut, lyeft fut!"
Also, Cersei's helium-level high pitched "My son!" as he dies is just a little hilarious even if it is rather sad.
Tyrion telling Shae they can no longer be together and that she has to leave King's Landing at once. It's supposed to be dramatic and sad, but it comes off like a very cheap soap opera.
The entire Dragonstone story in season 4, as it completely ignores the way these characters ended up in the previous season. You want to get a move on to the Wall, guys?
Ok, the reveal of the Night King and his method of creating new White Walkers was indeed pants-shittingly scary. This however was slightly tarnished by how the baby reacted to the most terrifying monster in the entire Game of Thrones mythos by grinning and giggling for a few moments.
The fact he looks a bit like an albino Darth Maul has made him a little less terrifying to some.
Karl's monologue about his backstory. Not only is it a blatant Info Dump with no real purpose, but even for this series the profanity in it is absurdly gratuitous, feeling like it was written by a teenager trying way too hard to be shocking.
The shamelessly blatant Plot Armor Ramsey Snow is wearing in episode 4x6, turning his back on several armored soldiers while not even wearing a shirt, while they all just stand around and wait for him to sic the dogs on them.
Arya trying to sound deep with her "nothing is just...nothing" line is more cringeworthy than profound.
Sansa's black outfit in "The Mountain and the Viper," complete with dyed black hair and a black dress with feathers. It's supposed to represent her becoming darker, but the fact it's so over the top can ruin the drama of the reveal.
Although the Mountain crushing Red Viper's skull is Nightmare Fuel in itself, it's ruined by the way the Mountain flops onto the ground beside Red Viper's corpse-they look like they're sunbathing!◊
Tyrion's "beetle monologue" is already notorious for this, especially when it goes on for about five minutes and is painfully obviously just there for Padding.
In "The Watchers on the Wall" when the giant shoots a man with its giant bow and arrow, the man practically gets launched into space.
Ygritte's death scene is undercut by a couple things: Olly's "I have your back" nod to Jon after he spent the majority of the episode cowering at worst, and operating an elevator at most was quite distracting. Then you have her last words being her Catch Phrase, which is narmy thanks to the amount of Memetic Mutation it's undergone.