"Happy Birthday, kids!"

It was a very particular date inside the Mystery Shack in Oregon, Gravity Falls. A party horn blew proudly while bundle of confetti blissfully rained on the two, surprised twins. One of the twins, Mabel Pines, a now 13-year-old girl with long brown hair wearing a pink, sparkly sweater, scratched the back of her head. She looked quite dumbfounded. She was typically the one to leap up in surprise and contain sparkles in her eyes jam-packed with optimism.

Grunkle Stan, a much older chap with aged hair, wearing a white undershirt with a red tie and black attire over it all, shrugged his broad shoulders," What? You all look dumbfounded. Today's your birthday!" He lifted his fuzzy eyebrow in curious confusion. He would've thought his nieces were proactive and knew it was their birthday today. He sighed roughly and felt disappointed.

"Yeah, man, you guys are finally thirteen." A teenage girl's voice popped up from the counter. She goes by the name of Wendy Corduroy. She had long, red-orange hair and was very tall. Wendy also wears a tan lumberjack hat with a touch of blue and black. She wore a green shirt with stripes and blue khakis. Her boots are coffee colored and are splotched with a darker shade. Relaxed and composed as usual, Wendy rested her arm on the shelf with the cash register on top," Looks like you guys are catching up with me."

The other twin, Dipper Pines, walks up to Wendy. He placed a big grin on his face and showed much gratitude on his countenance," Yes! We're technically a teen!" He turned around and had sort of a dreamy look on his face. Dipper has had a profound feeling for Wendy ever since he and Mabel moved to Gravity Falls. He was quite anxious to ask Wendy out at times, even when there's an opening chance. At a cue of a voice, Dipper and Mabel turned at a rather round guy with a green shirt and shorts," You dudes can get something out of the Mystery Shack free." The twins exchanged joyful grins with each other.

At the cue of "free", Grunkle Stan swiftly turned around with a disbelief look on his face," Free?" He quickly moved towards the overused cash register. He pressed a random switch and a small tray jumped out horizontally with the sound of loose change. He dug one of his big hands in the tray, later ending up with two $10 bills in his hands," Here's 10 dollars for each of you," He quickly gave each bill to Dipper and Mabel," Buy something and furnish the money back to me. Got it?" The twins got their cash and began walking here and there just about the full Mystery Shack.

After a couple of minutes passed, Mabel returned in the room with her pet pig, Mr. Waddles. They walked in and froze at the same time. Mabel motioned her arms in a drum roll and stretched her arms towards the pig, with a huge smile full of braces," Da-nu-nu-nu! It's a hat for Mr. Waddles!" Instantly, the pig beamed a cocky grin on his mug, pompous of his very own wacky, purple baseball cap.

On the other hand, Dipper returned, but couldn't find anything charming. He glanced around with a doubtful look, until he hooked his eyes on something appealing. He had other plans. He grabbed the gleaming objects and showed them to Wendy. With an astonishing look, Wendy stared down at the dazzling earrings Dipper held out in his hands toward her," Whoa, dude." She said in a low tone, shocked to the dazzling substance she sees before her.

"Do you like it?" Dipper asked arrogantly," I knew you always wanted those."

Wendy hesitated before beaming a smile on her face," I like 'em, Dipper. But remember, it's your birthday, not mines." She playfully rubbed her hands on Dipper's hat, ruffling his hair underneath. He let out a lighthearted laugh and looked into Wendy's eyes with fondness. He smiled brightly and kept his hands on the side of him, holding back from a warm, friendly hug that could utterly surprise the teenage high school girl.

It was noontime at 6:45 PM in Gravity Falls. The sun was mid-halfway in the deep blue and orange faded sky. The vast band of pine trees cast a deep shadow over the Mystery Shack, giving it a peaceful, hollow look. The usual noise of a woodpecker pecked on a piece of wood sounded in the cool, summer air. Inside the Mystery Shack, Stan, Soos, Wendy, Dipper, Mabel, and Mr. Waddles sat around the small like table with three light bulbs underneath a red-and-white striped plastic drape around it. In the center of the table was a cake-with weakly drawn design on it. It had sparkles and a rainbow on one half of the cake, and a video game joystick with a magnifier glass on the other side. Candles on the top of the cake were in the shape of a one and a three- resembling "13". Grunkle Stan cleared his throat in the utter silence in the room. Everyone had their eyes on the poor excuse for a cake.

"It's half sparkly and half nerdy," Mabel pointed out," I like it!" She seemed to be the only one actually proud of the cheerless cake. The other twin didn't say a word about the cake. He looked away warily and his cheeks heated up at the cake's embarrassment that wasn't amusing Wendy's.

Grunkle Stan shrugged his shoulders and spoke with disappointment," Couldn't discover a better cake designer than-"He paused, feeling like someone was after him. He swiftly looked behind his shoulders and saw an angered, young female with goggles. He stared speechless, realizing the cake designer was still inside the room," Oh sorry, you're still here?" He spoke.

They have seemingly sung "The Happy Birthday Song" before realizing the cake's horrible designs, so Soos spoke up and went straight to the point," Hey, Mabel, what is your wish?" Please don't be a talking horse, Soos added inside his head with a worried look on his face, but no one noticed to his relief. Without moments to waste, Mabel gasped. Today was time to share her major wishing beyond her other wishes. Now was the faultless time to share it!

"I know!" She spoke loudly with untamable eagerness," The wish I always kept to myself… will now be revealed!" Everyone around the table slowly leaned closer about an inch or two, their ears perked and ready to witness the biggest wish beyond all wishes…

"My wish is to be… in space!" She flew her arms up in the air with full exaggeration and bliss, she continued," I've always wanted to blast off and see other galaxies and matter! Always wanted to see new things! Galactic like! Or maybe even possibly find a rainbow, laser, sparkly super-unicorn-pony… that can talk! Then I'll be Mabel Pines: Queen of the Outer Universe!" Her eyes grew big, imagining her imagery on what deeper in superficial space would look like, breathing to catch her breath. Every individual had an incredulity gaze on their face.

Mabel chuckled at the quizzical eyes staring her down," Everyone is so quiet right now."

Dipper was the one to respond towards her hyperbolic imagination," Because it's illusory, Mabel. Maybe try to wish for something more lifelike and realistic." He tried not to sound too harsh towards his sister, but he was telling the truth. The imaginative twin looked down bashfully and sighed. She turned around and wrapped her arms around her chair in embarrassment. Dipper began talking about his only wish, which was to become a detective, but his speech was fading out as Mabel ignored his words of realism.

Dipper's right, Mabel thought, no way that'll every happen. He's being unusually mean, trying to impress Wendy. I'll prove to everyone that having imagination isn't a terrible thing…

Finishing up his wish, he ended with," …Thus becoming a world famous detective." Instantly startling the others with a thunderous clap of his hands, Grunkle Stan spoke loudly," Very nice. Now blow out the candles already. Or we'll burst into flames!" The others around the table stood speechless with round eyes. Grunkle Stan scanned his eyes around the stupefied crowd," Get it? Get it? Get… oh whatever. Just blow the candles already." He placed his elbow on the table with a loud thump, resting his head in the palm of his hand. Now was the time for an official birthday, waiting for the two, lucky twins to blow out the candles for the 13th time in their lives. Mabel turned back around facing the table and sighed sorrowfully. At the same time, the two birthday twins closed their eyes, leaned inward towards the cake and softly blew the candles out. After a moment's silent second, Grunkle Stand crossed his arms and smirked," Okay, let's-"

A loud, sudden blast plunged from the birthday cake, proudly ruined. It splattered in many directions like pie exploding from dynamite, sharing its tiny pieces onto everyone's faces. Traumatized expressions exposed on everyone's countenance as their terrified, bulging eyes lay on a rather scaly, reptile brute. His head was green like his spiky shell, his nose and around his muzzle was tan like his rough belly. The rest of his body was rather a tangerine shade and he had vicious claws, capable of tearing through solid. He gaped his mouth open wide slipping out a cocky boast as cruel as a child's. Everyone screamed, the monster roared, then everyone screamed again, and the monster spoke," Silence!"

Not afraid to speak out, though with a quavering voice, Soos spoke up," Whoa! It's a dino dude!"

"Who dare calls me by such idiotic, human dialogue?" The cake, covered creature looked both ways furiously until he could meet up with Soos. Mabel stared with big eyes," Who are you?" The infant reptile cackled a smirk," I'm Bowser Jr. And that's what you should call me for the rest of your lives!" He burst into a cocky laugh, placing his hands on his sides. Unlike everyone else, and the usual optimist in the group, Mabel placed her small hands on her blushing cheeks and spoke in a high voice of adoration," Aw… You're so cute!"

Bowser Jr. looked away shyly, yet irately as he hissed under his breath," Cute? Blah!" He spat on the floor.

"I don't remember a small monster being in the cake when I bought it." Grunkle Stan scratched his hairy, gray sideburn. Once again, he felt that weird, awkward presence of the cake designer. He looked from the corner of his eyes and grunted," Again, the presence. And how did you get up there?" Stan looked up and almost fell backwards in his chair when he noticed Bowser Jr. perched on the girl's head," Fools," he growled," I'll rip your shack from the roots!" The hot-headed reptile infant folded his fists in a ball and shook it intensely.

Full of confusion like the rest of the individuals, except for Mabel, Dipper was the one to speak next," What have we ever done to you?" He was oblivious of the horrific creature and was clueless at the moment.

Instantly, without warning, giant metal pieces-as if part of a gigantic metal hand-crunched and screamed into the Mystery Shack's ceiling. Booming noise, rumbling, and crashing all happened at once like a single action. Pieces of debris and wood cried harshly on the surprised people. Losing their balance with bewilderment, they each began scurrying around like tiny, frightened ants looking for shelter. A mechanical whirring sound started and stopped, started and stopped simultaneously outside the shack. its terrifying sounds really made Grunkle Stan worried," Let's get out of here!" He began running, leaving anything and everything behind him. He pushed and knocked everyone out of the way.

The scaly creature pointed his pointy finger at the bewildered crowd," You're tickling me! You'll never escape! Ha-Ha!" The Mystery Shack started swaying back and forth, with everything in the shack sliding one side of the shack to the other continuously. Mabel screamed and ran for her life, faster than anyone else. Her speed didn't take her away, but her mishap did. She stepped on a loose, weakened crack on the wooden floor and the pressure of Mabel's foot brought her crashing down. She perilously fell downward and screamed at the top her lungs," Dipper!" At the call of his name, Dipper called back," Mabel!"

He quickly stretched his arm out, but was too late to catch his twin. He leaned in further and fell right through the growing hole. He blistered his arm along the sharp corners of the hole and fell perilously as well. He fell fast enough to end up falling alongside with his sister, Mabel. They both fell down against the hard grass with a loud thump. They groaned in pain, but were unable to be heard over the terrifying crumble and creaking sound of the Mystery Shack soaring about the earth.

Still inside, Grunkle Stan ran against the door and knocked it furiously. After a couple of hard bangs on the front door, he yelled in a panicking voice," No! The doors locked! It can't be! Not today, world, not today!" He turned around and laid his back against the door, keeping his balance against the swaying of the shack. Sliding by, Soos landed harshly against the door by Stan's side," Well," he said," Wish I had a birthday party as epic as this." On the far side of the room, the cake designer girl waved a goodbye and spoke for the first time," See you!" She made a single wave with her hand in the air and took off hovering deep into the afternoon skies. A dual of propellers shot up from her mini book bag and flew her far away from Gravity Falls.

"Wait a minute," Grunkle Stan pondered before pointing out," Where's Wendy?"

"She was just at the table," Soos said," But what about the twins?"

Bowser Jr. leaped onto a window pane and looked back in the shack. He had successfully done his part in the job: Ruin the day. He chuckled mischievously and hopped out onto a long, metallic piece of equipment. The long mechanical staff was attached to a floating airship. The airship had slow, waving cannons jutting out from both sides. The cannons weren't armed with any weaponry or bombs whatsoever. A large propeller spun like crazy on the butt of the ship, allowing the craft to float with ease. A thick pole wedged outward from the inside of the ship, with a flag attached at the tip. The flag was a jet black color with a white reptile's face on it. It almost resembled Bowser Jr., but a much scarier one.

Making his way up swiftly across the metallic machine, Bowser Jr. made his way up and jumped inside the ship. He walked up towards a bigger version of himself with fiery hair and a bigger shell," Hahahaha!" The infant boasted," Victory is ours! Ours!" He folded his arms and turned his head towards the bigger brute," Dad! We got them! Now let's get out of this heap!" The large reptile had the same features as his "son", but with more muscle and he wore a black, spiky collar on his neck, shoulders, and wrists. The bigger form grumbled deeply in a flat tone," We've got her."

Lying sprawled on the ground alongside Mabel; Dipper lifted his body up weakly and rubbed the back of his head," Uh…" He groaned in a weak voice," Wh… Where's everyone?" Doing the same action, Mabel got up as well as she moaned dimly," Dipper… Everything feels empty-like around." She slowly shook her head, trying to get her focus back.

"Dipper! Mabel!"

A shrill voice screamed from the direction of the airship. Dipper and Mabel both looked up; suddenly their eyes grew big and bulgy. They've seen the figure of Wendy stretching out a hand in fear, standing in the gloomy airship. Bowser Jr.'s "dad" cockily walked up by Wendy's side, spreading his arms out in bragger," Princess Wendy Corduroy. You're with me now!"

Grunkle Stan and Soos still lay against the refusing door, unable to open. "Princess Wendy?" Soos spoke to himself quizzically. Grunkle Stan looked at Soos big eyed," What? I can't hear you over my bewilderment."

Dipper and Mabel both stood up quickly and folded their fists," What do you want from Wendy?" Dipper cried. Mabel added on," Yeah!" The bigger version of the infant reptile boomed his voice," Princess Wendy is all I want. I want no harm. We both shall rule the galaxy together!" With shock, Wendy swung her head towards the beast," What?"

Dipper folded his fists in a ball and stepped forward," We won't let you take her, you beast!" A surprised growl came from the infant creature," Huh!? My daddy has a name, you idiot!" The oversized, muscled reptile stomped forward once or twice in the ship and folded his arms boldly," Insignificant fool! I am Bowser: King of Koopas! You must respect me in full manner!" He laughed boomingly while his rock hard chest hopped up and down. The little Bowser Jr. bent down and raised back up, holding a plump pig," Looking for this?" He cackled and held the pig over the edge. The pig wasn't frightened; he didn't realize how major the situation was. Without hesitation, the koopa kid released the fat pig, causing it to plummet perilously to the ground to signify its death.

Mabel stretched her arms out in fear," Mr. Waddles!" She quickly dashed like a streak of blur towards the falling pig. She froze and stretched her arms high in the air, waiting for her pet to fall safely in her arms. In just a few seconds, Mr. Waddles landed hard in her hands with a shrill squeal. Mabel stood in perfect form, keeping in balance with perfection. She beamed a relieved smile full of braces on her face," Woo… got you!" Mr. Waddles wiggled his nose and snorted in response.

The mischievous infant creature hopped and poked his tongue out in taunt," See you never, suckers! Have fun crying on the ground with your pig!" Bowser Jr. turned after his last words to the twins and pig and walked towards the steering wheel of the airship. With the claw machine gripped onto the Mystery Shack and "Princess" Wendy captured, the airship began moving in motion towards the opposite direction. It took some time and effort before the gloomy ship sailed off into the sky, gaining speed, finally becoming nothing but a blurry dot in the afternoon sky.

Left unaided and isolated, Dipper, Mabel, and Mr. Waddles sat dumbfounded on the bare ground where the Mystery Shack once sat. With total eerie silence knocking the atmosphere with the airship totally gone, Mabel plopped back down on her bottom next to Dipper. She held Mr. Waddles tight in her arms, looking around every angle of him," Are you hurt, Waddles?" The dumb pig, still wearing his purple hat, snorted and wiggled his wet snout in reply. Mabel sighed in relief: No bruises or injuries on Mr. Waddles. That was good news Mabel was glad to hear all day!

Dipper was unmoved. He fixated his eyes at the sky where the airship left with his beloved- soon-to-be beloved. Rage and ire glowed in his eyes, frowning at the fact on what just happened. Still in the position, he spoke in a hard, low tone," Mabel, I don't know what just happened. But we'll try and find some help or clues." He paused before turning his back towards the sun. Dipper's silhouette was twice his size on the soil, yawning in front of him like a narrow gap. He folded his fists, shaking them intensely, trying to tame the fueling fire inside of him. Cooling down only a seldom bit, Dipper unfolded his hands, sighing out his last words before they all walked away:

"This is a birthday to remember."