Proving to us that even the unabridged version of Yu-Gi-Oh can have a couple of laughs.
In chapter 7 of the manga, Honda strangles Yugi not once, but twice. The first was when he thinks Yugi snickered after Jonouchi tells him that Honda was in love with Miho. The latter strangling ensues when Honda threatens to kill Yugi if he screws up on writing a love letter on a blank jigsaw puzzle that his grandfather had.
From the English dub:
Seto Kaiba: It's a new high-tech dueling device that allows players the realism of arena matches in any setting.
Joey: Looks like just a regular old briefcase to me.
Kaiba: It's in the briefcase, you moron.
Another one, from Ep 4:
Bystander 1: Whoa, sounds like a duel's going to start over there.
Bystander 2: That's Weevil Underwood, but who's the other guy?
Joey: That guy is Yugi Motou. He beat Kaiba. And I'm his best friend Joey Wheeler. (indicates Tea and Tristan) And these two? These two are trespassers.
The scene when Tristan, Tea and Bakura are climbing a rope into Pegasus' tower. Tristan wants Tea to go first so that he can catch her if she falls, but Tea complains, noting that she doesn't want them to look at her panties. Tristan's solution? Climbing up while blindfolded.
Made funnier when it's Bakura who has to explain that to Tristan.
The begining of the KC grand Prix. Kaiba says that anyone late to the opening ceremony will be disqualified. He then says to Mokuba, "Make sure Wheeler's late."
Basically, any time a character bursts into a monologue about how they've tricked their opponent, their card's hidden effects, the trap card they've just activated, etc, etc, only for the resident Deadpan Snarker to shut them up. "Yeah, I know what the card does."
The episode in which Yugi basically sets his Other Self up, by claiming he's meeting Tea - and then switching with Yami at the last possible moment. Yami's reaction as he realizes he's just been set up on a date, is priceless.
Yami (dub): Hey!! Yugi... I'm not... You can't... This isn't a duel!!!! (notices Tea is staring at him) Oh. (stands up straight and holds up a hand in greeting) Hello.
Not to mention Yami getting Yugi back in kind during the KC Grand Championship arc:
Joey: About that Underdog card...you said it reminded you of someone, right?
Yami: ...I did? Oh, yes...um...a little help here?
And his expression while laughing. Seriously, season 5 Dark Bakura is worse than Dark Malik in that regard.
One from the Japanese version is when Pegasus defeats Bandit Keith in a duel by telling a kid to follow instructions he wrote on a piece of paper. Keith's reaction when he sees the paper? "Oh my God! OH MY GOD!!"
Really just the first half of episode 2 in general, especially Grandpa's training session with Jounouchi ("YOU ARE NOT READY FOR THE TOURNAMENT YET!") and Jounouchi becoming overwhelmed with emotion and attempting to hug Grandpa... and failing, as Grandpa completely ignores him.
From Episode 168 of the English dub:
Seto Kaiba(to Yami): Stop saving the world and get a hobby!
Episode 68. Japanese version. When Jounouchi's parasite card fails to leech on Ryota Kajiki's card (and is, in fact, destroyed), Jounouchi's face combined with his shocked-calm voice had this troper giggling.
And Kaiba's incredulous comment to Yami: "This is ridiculous! You DO realize that you're talking to a hologram with your head on it?!" This, in the middle of a serious moment. Thanks, Kaiba.
Anyone else remember back in episode 18 when Joey was dueling Bones in that cave? And how his friends spent half the episode looking for him? First, coffins with skeletons that fall on Bakura and Tea... then Bakura chasing them with another skeleton draped on his back... and finally, Bakura stepping on a trigger that sends what appears to be a giant boulder that runs over the abused Bakura and almost corners them... until Tristan punches it... and it turns out to be a balloon with a speaker inside. Some of the funniest parts of Season One were all jammed into half an episode.
I liked Joey and Tristan at the end of Bakura's intro episode.
Joey and Tristan: *hug each other in fear* Bakura!!!
Tristan: Hands off.
Joey: You grabbed me.
Joey&Tristan: *takes a second before it sinks in and they push each other away* BAAAAH!
From the Joey vs Zigfried duel, when Zigfried uses his three Norns combo.
Zigfried: Looks like it's one underdog vs three divas!
Joey: You mean fournote Zigfried looks very camp. divas!
Joey's various insults to the bad guys, especially if they're bald.
In the manga when Yuugi mentions that their digital pets have the ability to mate and gain strength from each other (which is awkward in the first place) to which Jounouchi responds, "Yuugi and I must mate at once!" Honda comments in frustration that people overhearing might get the wrong idea.
One of my favorite exchanges, during the campout in Duelist Kingdom:
Yugi: Joey, I don't think we should cook the candy bars-
Mako's entire entrance, really: First a wave quite literally washes over him during his dramatic rant, then he's crawls back up the cliff, mortified: "All right, let's try that again". Then the "Freaky Fish Guy" line above, then Tea giggles at the fact that he has an octopus on his head from the wave. Mako angrily throws the octopus away, then Joey and Tristan scream that they wanted to eat it.
Easy with the technology, you spaz!
"Oh look guys, Joey named his chicken." "It's a Niwatori, Mai."
Bit of a Bilingual Bonus funny moment there: "Niwatori" is Japanese for "Chicken."
And what did Joey name his Niwatori? In the dub, at least — "Drumsticks."
During Yugi and Yami's final duel, Grandpa and Bakura do a happy dance.
Yugi beat the Pharaoh! Yugi beat the Pharaoh! Yugi beat the Pharaoh!
From episode 7 of season 2:
Joey: TRISTAN!! *groan* I'll kick your lyin' butt!
Seto's expression when Mokuba offers the others to fly home with them in the helicopter after Duelist Kingdom. They all squeeze into the backseat, and Seto just keeps grumbling all the time. Then Jounouchi almost falls out when he kicks a ladder down for Mai.
I know the dub abruptly cut the ending of the original anime short but, the last lines between Kaiba and Joey are the some of the best lines in my opinion.
Tristan: So this is the end? Feels weird.
Kaiba: What were you geeks expecting?
Joey: Fireworks, sappy music...something.
The best part is, Joey doesn't even snap at Kaiba. He just mildly lists a few common Happily Ever After cliches!
From the scripted duel between Yami and Yusei's VA's (see the Awesome page for a link), we get this exchange when it's over:
Yami: I do have one question. What's a Duel Runner for? Yusei: Well, actually, I like to think of it as card gameson motorcycles.
During the KC Grand Prix where Joey nearly gets disqualified in his duel against Mask the Rock because he's too busy eating. Then when he learns he's supposed to be up next, he runs halfway across Kaibaland taking the rest of the gang with him to get to the place of his duel and just barely makes it in time, only to discover that Mokuba has already arrived there ahead of him by taking the back way!
And in the Battle City arc, we have the most amusingly blunt response in the entire (monologue-heavy) series:
Marik: My name is Marik.
Yami Bakura: I don't care.
Princess Edina: a female Mokuba who shows up in the Duel Monsters Quest episodes. As pointed out by Joey, the fact that she looks like Mokuba reflects the game's creator vision of him. In the original, the game was created by the Big 5 (so they basically see their VP as a helpless sacrificial princess). Already pretty funny, but the dub takes it Up to Eleven, since in the dub, the game was created by none other than Seto Kaiba.
The "Noah Arc" had the Big 5 only claim Tristan's body out of the five duelists they faced, putting Tristan's soul in a robot toy monkey, "Acrobat Monkey." The final battle has the Big 5 taking turns facing Yami Yugi and Joey in Tristan's body. Tristan himself is horrified the Big 5 are treating his body that way:
Tristan: Those guys are passing around my body like it's going out of style!
Tea: I can't believe that all of the Big 5 are in Tristan's body!
Tristan: Those business creeps are sharing me like a corporate condo!
Seto Kaiba is in brilliant form throughout the Doma/Waking The Dragons arc.
After Yugi's Heroic Sacrifice, the gang are trying to get a ride to save him. Without any real options, they call up Kaiba ("...It works better if you move away from the webcam...") and ask him to lend them a helicopter. Kaiba then learns of the previous events and proceeds to go berserk, screaming into the phone at Yami, who is practically catatonic at this stage. He's not angry with him for losing Yugi's soul, of course, but because he lost his title as King of Games to a nobody.
Later, when he teams up with Yami to duel Darts, Darts plays a set of Mirror Knights that have the faces, and supposedly souls, of Yami's lost friends. Destroying the cards means destroying the souls...apparently. Yami refuses to take the risk of hurting them, but Kaiba can't help himself and trolls Yami ("You do realise that you're talking to a hologram with your head on it, right?") while cheerfully destroying all the knights' shields.
Kaiba: So you have a geek army. Is that supposed to scare me?
Dartz: Only if destroying an innocent soul concerns you.
Kaiba: Nah. As the president of a major company, I have to do that every day.
Eventually, upon realizing that Yami won't attack the cards, Kaiba frustratedly points out that it's just not possible for the souls to be lost simply because a hologram of them gets destroyed—and he knows this because he helped make that holographic technology. Yami still won't do it, and ends his turn without playing a card. Kaiba's reaction is utterly priceless.
Kaiba: Please tell me you are joking.
Later still, when Yami summons the Egyptian God Cards, Joey proceeds to call out their names as per usual, just in case we'd forgotten them in the past two minutes or something. Kaiba quickly shuts him up.
In Freeze Play part 2, Tea falls unconscious and has a dream. The first part of it goes like this:
Tea: Hey Yugi! I had a dream we were trapped in a virtual world and we had to duel five old guys to escape!
Yugi: Actually, Tea, this is the dream. And when you wake up, you'll need this card. *hands Tea the Dark Magician Girl*
Tea: I will?
Yugi: It's the Dark Magician Girl, remember? There was a Broadway play about this card - we saw it a few years ago!
Tea: We did?
Yugi: Weelll, not really, but this is your dream, so just go with it.