I will tell you this story about the Koopas' first Christmas. Yes, the first. Bowser never bothered to tell his kids about Christmas.
Mario: Mama mia! It's Christmas Eve! I didn't buy anyone any gifts! Oh well! I'll just buy them some cheese and some naughty ponies!
Larry (who just happened to be spying on Mario): Christmas? A holiday where you give and receive presents? I must tell the others!
At Castle Koopa...
Larry runs into the Game Room. Ludwig, Lemmy, Roy, and Iggy are playing Super Smash Bros. Brawl. Wendy and Morton were watching.
Larry: Hey sibs! I need to tell you something!
Roy: What now?
Larry: I was spying on Mario, and he was talking about this holiday called "Christmas", which is tomorrow!
Ludwig: And what do you do on Christmas?
Larry: You buy gifts for people and they buy gifts for you.
Lemmy: Why haven't we ever heard about it?
Morton: Maybe King Dad secretly does this, but instead of buying for others he just buys presents for himself. He must think we are dumb, stupid, unsmart-
Wendy: SHUT UP, MORTON!
Iggy: Morton might be right, maybe King Dad didn't bother to tell us because he's too lazy to spend money on anyone but himself.
Ludwig: That gives me an idea! We can celebrate Christmas and not tell King Dad about it.
Lemmy: What else do-
Iggy: -we do?
Ludwig: We buy presents for each other and for King Dad. He'll be wondering why we bought all of these presents. Boy, am I smart!
Larry: Let's do it!
The Koopalings run through the snow and chop down some random tree to be their Christmas tree. They run back inside and place the tree in the Game Room.
Roy: Why the Game Room?
Morton: Because we already have lots of goodies in here.
Roy: Uh, OK.
Ludwig: Let's get our money and go to the Dark Land Mall.
The Koopalings grab all their money and run to the mall.
Ludwig: Now, we will each buy one present for each of us, except for yourself. We'll also buy a gift for King Dad.
The Koopalings run in different directions and buy presents.
With Lemmy...
Lemmy: I wonder what my siblings and King Dad would want.
Lemmy thinks for 10 minutes, and finally decides.
Lemmy: I've got it!
Lemmy runs off and buys the gifts. He actually gets some really cool stuff.
With Iggy...
Iggy: I know what to get for everyone but Roy. This will take some time.
Iggy's mind goes blank for a long time. Finally, a Koopa gives him ideas.
Koopa: Why don't you get your brother something simple, like a wrestling magazine or something like that?
Iggy: I like your style.
With Roy...
Roy: I bought everyone a present except for that twerp Iggy.
Roy thinks about what he should buy for Iggy.
Roy: Well, it's Christmas. I'll be nice to him for a little while.
With Ludwig...
Ludwig: Wow! It only took me 5 minutes to buy presents. A new record! My only record.
Ludwig goes back to the castle to wrap the gifts and place them under the tree.
With Wendy...
Wendy: Well, I don't know what my brothers would want since I don't care. I'll just buy gifts for myself. They probably won't even notice.
Wendy does so.
With Morton...
Morton: Why buy gifts? I can just make my own! I know my siblings love my speeches! Oh well, they may complain.
Morton decides to buy gifts for his siblings just in case.
With Larry...
Larry: With my skills, I can just steal gifts... or maybe not.
We see a flashback from the time Larry stole a Piranha Plant from the plant store and was caught. He was sent home and got in big trouble since it had nothing to do with Mario.
Larry: OH NO! Anything but that!
Larry buys the gifts so he doesn't have to worry.
Later that day...
Bowser has been sleeping through the whole story so far. Now he decides to wake up. He walks past the Game Room and sees a tree with wrapped gifts under it.
Bowser: What the? Why is there a big tree in there?
The Koopalings are in the Game Room continuing their round of Super Smash Bros. Brawl.
Bowser: Why do you have a tree in here?
Lemmy: It's-
Iggy: -Christmas Eve.
Bowser: Oh no.
Wendy: Now you must buy gifts for us.
Bowser: No.
Wendy: I WANT CHRISTMAS PRESENTS! I WANT CHRISTMAS PRESENTS!
The other Koopalings join in, yelling "US TOO!"
Bowser: OK! FINE! I WILL!
Later that night with Mario...
Mario is at his house with Luigi, Yoshi, Toad, Princess Peach, and Princess Daisy.
Mario: So, what did you buy me for Christmas?
Peach: Why should we tell you?
Mario: Because I said so!
Luigi: Just wait until tomorrow.
Mario: No.
Daisy: Yes you can.
Mario: No.
Yoshi: Mario can wait.
Mario: No.
Toad: Yes you can, Fattie!
Mario: No.
Others: SHUT UP!
Mario: No.
Mario is thrown out the window for no reason at all.
Peach: Let's get out of here!
At Castle Koopa...
Bowser: All right kids, go to bed or no presents.
The Koopalings run to their rooms as fast as they can.
Lemmy: I can't wait!
The next morning...
Iggy: PRESENTS!
The Koopalings run to the Game Room as fast as they can. Bowser walks down 5 minutes later. He finds the Koopalings opening their gifts.
Lemmy: Wow! A new laptop from Iggy!
Iggy: Wow! A collection of video games from Lemmy!
Lemmy and Iggy: You're the best brother ever!
Larry: Yay! I got the Nintendo DSi! Thanks, Ludwig!
Iggy: Huh? To Iggy. From Roy?
Iggy opens the present and finds something that actually doesn't harm him.
Roy: Merry Christmas!
Iggy: Really?
Roy: Sure.
Ludwig: Nice! A fossil! How did you buy this, Morton?
Morton: I paid someone to dig a hole for me.
Ludwig: Well, that's interesting... and kind of weird.
Wendy: I didn't buy you guys anything because I didn't want to.
The other Koopalings make angry faces at Wendy.
Lemmy: Let's see what the rest of us got.
Ludwig: I got a fossil, an ancient Goomba tooth, a Bob-omb maker, a book on how to compose, and "Make Successful Inventions for Dummies" .
Lemmy: I got a new ball, a new laptop, lots of video games, an ice cream machine, and Super Koopa Bros. figurines.
Roy: I got a wrestling magazine, "How to be Nice for Dummies", boxing gloves, a punching bag, and some shades.
Iggy: I got a new pair of glasses, a collection of video games, Super Koopa Bros. figurines, Super Koopa Bros. trading cards, and a taco machine.
Wendy: I got you guys nothing, but I got a bunch of girly stuff from you guys.
The other Koopalings make angry faces at Wendy again.
Morton: Congratulations. Anyway, I got a bunch of stuff I can talk about all day! I got a recorder, a book with lots of words, a movie with lots of talking, a game with lots of talking, and "101 Reasons Why I Should Shut Up".
Larry: I got a plant, a Nintendo DSi, games for my DSi, a camera, and a table with different mini sports to play.
Ludwig: What did you get us, King Dad?
Bowser: What?
Ludwig: Christmas presents?
Bowser: Oh, uh, about that...
Luigi, Peach, Daisy, Yoshi, and Toad show up.
Luigi: Merry Christmas!
Bowser: Excuse me?
Peach and Daisy: Merry Christmas!
Bowser: Eh? Speak up, Sonny.
The Koopalings exchange looks with each other.
Toad: MERRY CHRISTMAS, YOU OVERWEIGHT KOOPA! MERRY CHRISTMAS! YOU HEAR ME?! NOW GIVE US PRESENTS!
Bowser: No.
Yoshi: Bowser give presents.
Bowser: No.
Luigi: He's acting just like Mario...
Mario walks in.
Mario: BIG MAN!
Bowser: What?!
Mario: I see why these cheese grits are yo favorite!
Bowser: Uh... yo?
Mario: I watch lots of TV. Someone hasn't watched TV lately.
Bowser: *mumbles* Weirdo.
Mario: GIVE ME PRESENTS! I ONLY GOT ONE PRESENT FROM YOSHI AND NOTHING ELSE! IT'S NOT FAIR SOME PEOPLE GOT LIKE 50 GIFTS!
Peach and Daisy look at each other and smile.
Peach: It's not our fault we're spoiled!
Daisy: Yeah! Is there a problem, Mario?
Mario: I'm not spoiled.
Lemmy: Haha!
Iggy: Haha is right Lemmy. Wendy is spoiled and she didn't get that much presents.
Wendy: Hey!
Lemmy: Haha!
Mario: GET THE GIFTS!
Toad: Nah, not interested.
Lemmy: Haha! I mean, NOOOOO!
Mario grabs as many gifts as he can carry and runs off.
Ludwig: Hey! Get him!
Luigi: Should we even bother to help Mario?
Yoshi: Nah.
Peach: Let's just go to my castle!
Daisy: Sounds good!
Peach, Daisy, Luigi, Yoshi, and Toad head off to Peach's castle.
With the Koopalings and Mario...
The Koopalings chase Mario and eventually go to his house.
Roy: Why did you steal our gifts?
Mario: I told you, I'm not spoiled.
Larry: Whatever.
Lemmy: Haha!
The Koopalings easily take the gifts back.
Morton: That was easy.
Back at Castle Koopa...
Ludwig: So King Dad, what did you get us for Christmas? You didn't tell us.
Bowser: Uh, about that...
The Koopalings: GASP!
Iggy: He didn't get us anything! Get him!
The Koopalings somehow pick up Bowser and throw him in the dungeon.
Lemmy: You stay in-
Iggy: -there, Big Man!
Bowser: Grrr... BIG MAN?
Iggy: Yeah, problem?
Larry: Didn't Mario say Big Man too?
Ludwig: Yeah.
Roy: Wendy didn't get us anything.
Morton: Throw her in there too!
Wendy is thrown in the dungeon.
Lemmy: You stay in-
Iggy: -there, Little Man!
Wendy: LITTLE MAN?
Iggy: Whoops.
Ludwig: We hope you learn your lesson. Have a Merry Christmas!
Morton: Here, you can have your gifts so you won't be bored. Don't forget to write!
The rest of the Koopalings go back to the Game Room and play with their gifts.
...
The Koopalings walk onto a stage. Wendy and Bowser are there too.
Lemmy: Why are you here?
Wendy: We are here for the ending.
Lemmy: Fine, but you must return to the dungeon after this is over.
Iggy: Ready...
The Koopas: HAPPY HOLIDAYS TO ALL!