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While the Ocean Group version of the line is better known, the Funimation version (which is the version Team Four Star chose to parody) is pretty silly itself, although that might have been done on purpose to lightly parody the original version.
Adult!Goku's Japanese voice is Narmful. It's dissonance to hear this big bad martial arts guy (a grandfather in the end) speaking with almost the exact same voice he had as a twelve-year old. (But then, this may have been intentional.)
Masako Nozawa as Adult!Goku is bad, but not as bad as Masako Nozawa as his father Bardock. A hardened, ruthless Saiyan warrior sounding like...this? That's so unfitting, it's hilarious!
Take a look at this scene in Dragon Ball GT where Gohan cries out to Piccolo, who is killed by staying on Earth as it explodes. If he were still a child, it wouldn't be so strange, but as a grown man?
Frieza tries to intimidate Krillin:
Frieza: You cut off my tail, you imbecile, and now I'm going to eat you!!!
A LOT of Frieza's Season 3 dub dialogue was Narm. A shame, since Linda Young was at her vocal peak here and final-form Frieza sounded semi-masculine!
The dub of the Dead Zone movie (one of the infamous European dubs which refers to Piccolo as "Big Green") has this line uttered by Big BadGarlic Jr. when Kami appears to confront him:
Garlic Jr.: Good lord, it's God!
From the same version, the Quirky Miniboss Squad are impossible to take seriously. While there's an element of parody with most evil minions in the Dragon Ball franchise, giving one of them a voice that sounds like an evil version of Fozzie Bear doesn't help much.
Because Dragon Ball in general and the Super Saiyan transformation in particular have been so mercilessly parodied over the years, the second version of the Dragon Ball Kai opening sequence, in which Goku suddenly transforms while fighting Frieza, could be retroactive Narm.
The way Frieza is beaten by Goku on Namek. As Goku is flying off and leaving Frieza cut in half and bleeding to death, Frieza starts screaming "I will make you pay for opposing the MOST POWERFUL BEING IN THE UNIVEEEEEEEEEEERSE!" and shooting a beam of energy at Goku. Goku turns around, screams "YOU FOOOOOL!", and blasts it back. Then Frieza's face and the way he's screaming makes it look like he's having an Immodest Orgasm. Also, Frieza says that he's "the most powerful being in the universe" about five times throughout that scene — the scene in which he is dying...
Before that, there was the scene in which Frieza sent one of his Chasing Destructo Disks at Goku. The camera spins around and around Frieza while he's laughing.
"You think I'm stupid enough to fall for such a childish TRICK?!!!!" The way Frieza screams "trick" and the way his eyes bug out are hilarious.
"Round and round the monkey goes, when he shall stop then OFF WITH HIS NOSE!"
This line by Captain Ginyu in the original dub as Goku is powering up to what was then considered insane levels.
Ginyu: "One hundred thousand?! Ay-yi-yi! I wasn't counting on this!"
Dragon Ball GT had a villain named Baby. This led to a plethora of lines such as "I don't think so, Baby!"
Though, this is noted in-universe too. Goku even jokes that Baby was sleeping like a baby.
Also during the Frieza Saga: Vegeta awakens from a much-needed nap and then finds the Dragon Balls missing and the dragon summoned. His reaction to the sight of the monstrous Porunga in the initial dub? To proclaim "Holy Cosmos!" and "That's one whopper of a lizard!"
Later episodes would give us such gems as "Great galaxies!" and "Son of a Namek!"
When Gohan is practicing with the Z-Sword, his practice basically includes swinging it wildly over a lake. But then occasionally, he'll stop what he's doing, hold the sword over his head, point to it, and scream, "HOOOOOOOOOOOOOOOOO!"
Kyle Hebert's deep narrator voice can sometimes lead to Narm, like in the episode Gohan Goes To Highschool where he says in his standard, Don Lafontaine-esque tone, "Hurry, Gohan! You'd hate to be late to class..." This is immediately followed by the title card with the standard "guitar riff episode title" theme. Basically, a rockin' guitar riff set to white text saying "Gohan Goes To High School".
The opening narration for one of the Cell saga episodes, picking up after Cell absorbed almost the entire population of a city. It went something like this:
"Just another ordinary, peaceful morning in a quiet little town, right? WRONG."
The English dub of Kai has Raditz shrieking "NOW DIIIIIIIIIIIIIE!!" before trying to kill Gohan. With a scream and hair like that, he could've been lead singer for an 80's hair metal band!
In GT, Vegeta's sad, sad attempt at growing a mustache. Even his daughter made fun of it.
And how could anybody forget this gem from the Funimation dub:
Gohan: Daddy? Turles: Huuuh? Whaaat? I see. So you are the son of Kakarot. You inherited the blood of Saiya-People! Gohan: Wh-wh-wh-who are you?! Turles: Huuuh? I am da Saiya-People! Gohan: Whaaa? The Saiya-People?! Turles: Yaaaaas! My name is Turass! We can wander selfishly in universe destroy whatever we like... Eat delicious food... And drink delicious likka! There is nothing like this enjoyable life!
This dub even has its own Engrish version of the infamous "Let that child alone!" line from the "Big Green" dub:
Piccolo: Take you hands off from Gohan!
Arguably, Piccolo's next line is even worse, ending with a roar that sounds like he tried to record it while gargling water.
Piccolo: I'm not KIDDING!!!! GUAAAAUAUAAAAAAAUGHGHHHH!!!
Anything Yakon does. Basically, one of the most dangerous species in the galaxy is called dumb by Goku.
It's just, he gives off a rapey kind of feel...
At the end of the fight, Yakon tries to kill Goku by eating his energy and turning into a balloon. It fails spectacularly.