Episode 2 has Kirby kicked out of the castle by Dedede. His friends try to build him his own house. After many trials and much tribulation they succeed, only for Kirby to take up residences in the tree nextdoor! Though the bird he'd stolen the tree from seemed happy with it...
In "Un-Reality TV," Dedede uses his televisions to brainwash almost everyone into attacking Kirby...including Kirby himself.
In "The Fofa Factor," after Kirby gets split into small male and female versions of himself, Escargoon comments that everyone probably has a male and female side to them. This leads to both Escargoon and Dedede imagining what a female version of the other character would look like. This makes them both shudder.
Moments later, this split ends up happening to Dedede. The two sides promptly freak out.
Meta Knight kicking Dedede's car down a hill—after saying he was his most loyal servant.
Although mostly known for its appearance in the Japanese version, Dedede and Escargoon's bickering as the car rolls down the hill in the dubbed version is good as well-
Meta Knight: Sire, it is my duty to warn you. Kirby has great power, now.
Dedede: Yeah? Well who's the King around here, you or me?
The first time Kirby becomes Mike Kirby in episode 31. Even after warping him to their headquarters, seven monsters (ones often seen in Meta Knight's flashbacks) that were eagerly waiting to come at him with their jaws open found his singing too much for them to handle and explode from the pain suffered by hearing it, and the NME Saleguy had to send him back.
Prior to Kirby, though, the Cappies were trying to sing oldies songs. Even earlier, Escargoon sang "Hound Dog".
The entirety of the pie episode, with almost everyone in the main cast getting hit by a pie in the face at least once. Even Meta Knight.
Even in the dub, right after that happens, he glances to the side and announces, "I feel...dirty."
The end results of episode 49 (Cartoon Buffoon)- Dedede Comin' At Ya! (Hoshi no Dedede in the Japanese version.) In case you're wondering: It's a half-assed, poorly written, hilariously hammy version of the first episode of the anime, except Dedede is Kirby and Kirby is the Demon Beast. Hilarity Ensues
Hell, the whole thing. It's filled with a ton of subtle and not-so-subtle jokes about animation.
Really, Meta Knight's status as The Comically Serious lends itself well to these kinds of moments. Another example would be in Episode 61 (Fitness Fiend), where everyone else breaks into dancing with Max Flexer (Macho-San in Japan) while he just stands there stiffly.
Fitness Fiend, where NME saved the day by working Kirby out.
Kirby ends up eating a whole pack of Gijira extract, which is a spice or a hallucinogen (depending on which version you're watching). Once Kirby swallows the entire pack, he thinks EVERYONE is food, and ends up preparing cooking utensils with the intention of eating everyone.
Dedede's attempts to avoid Kirby after having several nightmares about the pink puffball in Part 1 of Prediction Predicament.
In the first episode, the mayor and the rest of the Cappies hold a feast for Kirby's arrival. Kirby then proceeds to eat the entire table of food using his inhale ability (Including the tablecloth and utensils!), leaving the rest of the guests in utter silence.
Dedede revealing and talking through his wonky painting in Dedede's Monsterpiece-
[Points to his tiny castle, and a giant misshapen-looking Escargoon next to it] Right there is my castle, and right next to it is Escargoon. Note the lack of depth!
[Points to an awkwardly-angled version of the Mayor with noodle arms and two giant angry Pac-Man-like sheep behind him] This here's the Mayor being chased by his sheep, [Points to a misshapen Kirby in the corner of the painting] and this here's Kuhbeh. He's being chased by me! See, I drawed him all lumpy to express his inner lumpiness!
Even better- when everyone does break down in laughter at it, Kirby is the only one not laughing- he's still glaring at Dedede in a hilariously-angry way over being called lumpy!
It's even funnier in the original version because that's NOT the reason Kirby gets mad at him. The real reason is because Dedede drew Kirby shitting himself!
Dedede's twisted version of "Old Macdonald" from Kirby's Egg-cellent Adventure, which he sings at a ridiculous speed as he's using his tank to draw a giant picture of Kirby eating Dyna Blade's egg (Complete with big goofy grin and oversized knife and fork) to get the giant bird to attack him-
And later on in the same episode, when Tiff asks Meta Knight for advice on the matter. What really sells it is Tiff's "WTF" tone and expression upon hearing his reply, in the middle of a mostly-serious scene-
Tiff: Help us Meta Knight, we've got to do something!
When Kirby has a nightmare in "The Pillow Case" (the very end,) he jumps out of his bed Hanna-Barbera style screaming and runs out his house, then stops when he realizes he's awake. Meta Knight also cuts a pillow in half revealing Noddy (the episode's NME monster.)
"I need a monster to CLOBBER THAT THERE KIRBY!"
"That's what we do best at NME!"
"You better get it with a money back guarantee!"
In "Something to Sneeze At", Dedede finally gets a cold. His reaction is to run around Cappy Town announcing he has a cold. "I love having a cold!"
In the "Kirby of the Stars" prototype/pilot, Ice Kirby uses his ability to freeze Dark Matter solid...who just stays where he is with an expression that just says "I am so done with this puffball and his shit"◊. He keeps this expression as he's being frozen, and casually just falls out of the air when he's frozen entirely.
In "Hatch Me If You Can", when Kirby chases after the egg, the egg ends up where Rick is holding a leaf umbrella to sheild Rick from the rain. Then the egg lands on Rick's head. Rick's expression before the egg hits Rick on the head is priceless. After that, the egg lands behind an unconscious Rick, with Rick having a Cranial Eruption. When Kirby reaches the egg, Rick comes to and after recognizing Kirby, Rick says this:
Rick: It's rainin' cats and dogs, but I never thought an egg can drop on me head.