At the very beginning of the film, Marlow's encounter with Gunpei during World War II, as Marlow pulls out his sidearm first and proceeds to miss every shot. Gunpei's brief baffled reaction and Marlow hightailing out of the beach is what sells it. The rest of the scene can be described as Marlow running away from Gunpei's sword.
If you listen to the bangs and clicks as Marlow flees, you can hear that Gunpei apparently empties his pistol without once hitting his target, either. Nice bit of not so different Foreshadowing for their later friendship, there.
After learning of Kong's true nature, upon rewatch the way Kong reveals himself to the two seems almost reminiscent an adult annoyed at their rest being interrupted due to needing to put an end to another fight breaking out between children.
Randa's first line of the movie as he and Brooks arrive at the White House amidst protesters calling for Nixon's impeachment. All that's missing is for him to look directly into the camera and audibly say the word "wink".
Randa: Mark my words, there will never be a more screwed up time in Washington.
And then cue King of the Monsters, where Washington has been completely leveled by King Ghidorah.
Randa and Brooks try to convince a cynical senator to fund their expedition.
Senator: As far as wasted funding goes, MONARCH ranks just behind the department trying to prove aliens exist.
Could also serve as some hilarious foreshadowing to King Ghidorah's debut in two years.
Conrad's bit as he's being recruited by Randa and Brooks:
Conrad: (deadpan) An uncharted island. Let me list all the ways you're gonna die. Rain... heat... disease-carrying flies and mosquitoes ... and we haven't started on the things that want to eat you alive.
Mills making fun of Chapman's letter:
Mills: Dear Billy, I know I said I'd be home by your birthday, but I lied straight to your face. I'm a terrible dad. I hope this letter makes up for it.
Chapman:(laughing) That's too short. (the both of them crack up)
"Dear Billy" becomes a Running Gag for them, both to show their affection for each other and to make a sit-rep of what they're thinking at the moment.
Mills: Cole, what's wrong with you? How you even got an appetite right now?
Cole:(shrugs) Eating's for the living.
Mills: We just got taken down by a monkey the size of a building!
Cole: Yeah. That was an ... unconventional encounter.
Cole brings up The Lion and the Mouse ... only to show he was told it wrong.
Cole: No, the mouse kills the lion with the thorn!
Mills: Who told you this story?
Cole: My mother.
Mills: (beat) That actually explains a lot.
When Packard asks Randa to explain what the hell is going on at gunpoint, the latter replies with a completely deadpan "Monsters exist." Packard's response? A sarcastic "No shit."
The "fight scene" between Kong and the Mire Squid, roughly a third of the way into the movie. It initially looks like it's going to be an epic battle... except, nope, it's a total Curb-Stomp Battle that Kong wins with about two or three blows. Plus, Kong picked that fight because he wanted a snack, which is shown in the way he messily devours some of the tentacles before dragging the rest of the carcass elsewhere to eat.
He even steps on the squid's body, making it explode in a wonderful mess of gooey black ink. All the while as Chapman stares in disbelief.
"You're more beautiful than a beer and a hot dog at Wrigley Field on opening day... the difference being that you're real... and here." Doubles as a Brick Joke as the credits shows he finally gets the beer and hot dog as well as baseball on TV when he returns home.
When Marlow is questioned on why he calls the "Skullcrawlers" exactly that...
On that note, him asking if they left Neil Armstrong on the moon.
The dialogue once Marlow asks if the Cubs have won anything since his disappearance. It's doubly hilarious because just a few years after he was stranded, in 1948, the Cubs got to their last World Series until 2016, when the team broke a record 108 years drought.
There's another baseball in-joke in the scene as well: when Slivko laughs at the idea, an annoyed Hank asks if Slivko's team, the Detroit Tigers, won the pennant that year, then brushes him off when he stammers no. Although the Tigers did win in 1968, at the time they were still under Billy Martin's very rocky management, and in the midst of a dry spell they wouldn't fully recover from until the '84 Series.
There are many, many signs that Marlow may not be right in the head after all his time in the jungle, but the kicker comes when he's shaving:
Marlow: I can't tell when I'm talking or when I'm not talking.
Nieves:(Fidgety) You're talking.
Marlow: Am I?
Nieves: Yes.
Marlow:I'm talking?
Nieves: YES.
Marlow: But your mouth is moving.
Nieves: What?
Marlow:(Softly, with his best Kubrick Stare) I'm gonna stab you by the end of the night.
Marlow is in the middle of telling the group about his wife and son, whom he has yet to meet. Then the following exchange happens:
Marlow: We got hitched right before I deployed. Got a telegram from her the day I got shot down. She said we just had our baby boy. I got a son out there. Grown man I've never met.
Slivko:(from the roof) Yeah, she definitely thinks you're dead, man.
Conrad:(hits the ceiling with an annoyed look on his face)Hey!
(The others shake their heads, while Weaver rolls her eyes)
After meeting up with Packard's group, we have Marlow jovially telling the soldiers how screwed their chances of survival are.
Marlow: This is a good group of boys. We're all gonna die together! (strained laughing) You shouldn't have come here!!
The grand reveal of Gunpei and Marlow's makeshift boat ... which is basically a bunch of scrap metal and engine parts welded together to create something that is barely floating.
Conrad: (in a completely deadpan voice) Well, that's lovely.
Crosses over with heartwarming, but Weaver taking pictures of the Skull Island natives and getting some of them to stoically do the peace sign.
The group comes across the open grave containing the remains of Kong's parents. Marlow tries to warn the group away from the valley, but Packard insists on going through.
Marlow: I've only been here twenty-eight years, what do I know?
Randa's death is darkly humorous. From his last words being "Oh shit" to his camera continuously flashing inside of the Skullcrawler afterward, almost as if he's taking pictures as he slides down its gullet. Crosses over with Nightmare Fuel when that flashing becomes the only thing giving the Skullcrawler away.
When Lin attempts to open a can of food, Brooks offers to do it for her and immediately cuts himself. After successfully opening it herself, she slams the can down between them with a satisfied smirk.
Marlow warning Brooks about the dangers of the jungle:
Marlow: Keep your eyes out. Up in the trees, too.
Brooks: Why?
Marlow: Ants. Big ones.
(Strange chirping sound; Brooks and Lin look around)
Marlow: Hear that? There's one. Sounds like a bird, but it's a fuckin' ant.
The whole conversation was ad-libbed by John C. Reilly.
Packard's last words: "Die, you motherfu—"
Despite having been brought down with a lake full of napalm, and the two established as mortal enemies, Kong still seems to regard Packard himself as little more than an annoyance, abruptly crushing him under his fist like he's hitting the snooze button on an alarm clock.
Also, the inherent humor of killing a character played by Samuel L. Jackson in the middle of saying "motherfucker".
During Cole's Heroic Sacrifice, the Alpha Skullcrawler almost seems to shoot him a look that says "How stupid do you think I am?" which it then follows by batting him away with its tail.
"Unless they were eaten by something that's bigger than us."
Even funnier in a meta sense when you realize Tom has already done something like this (in character as Loki) during a Comic-Con Panel while promoting one of the Thor films.
The hilarity is enhanced if you're in a theater where all of the remaining audience members answer him back.
And continuing from this scene.
Conrad: Look, we get it. We promise we won't tell the Russians.
Nieves's demise, as horrible as it is, is rather hilarious. He gets dragged off by the tiny pterodactyls kicking and screaming, still determinedly hanging on to the briefcase. Then, as their silhouettes are framed against the sunset like a shadow puppet play, Nieves' left arm, still holding the briefcase, falls off.
Kong slams a boulder onto Ramarak's head as if he was dunking a basketball!
When Ramarak is about to finish off a trapped and chained Kong, the humans intervene by distracting Ramarak with gunfire. He gives chase and abandons Kong...but not before bitch-slapping Kong with his tail.
Kong wields a boat propeller like a blade on a chain, almost like Kratos from God of War!
It's in the middle of the dramatic scene where the gang is trying to convince Packard to not kill Kong. Weaver begins making a heartfelt speech in defense of the big guy. Packard's response is classic Samuel L. Jackson.
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