One chilling day, evil laughter echoed throughout the villainous Doctor Eggman's Lair as the devious scientist was working on another sinister scheme within his lab. Orbot and Cubot were in the room too, waiting to see the results of Doctor Eggman's newest plan.

"Today is the greatest day in supervillain history, my evil minions." Eggman declared boldly as he showed off his newest machine that he'd just invented, "I have created a multiverse portal generator that shall enable me to reach out into the multiverse and partner with a villain the likes the world has never seen. And with his help, I CAN FINALLY CRUSH SONIC!"

Without another word, the devious scientist turned his attention to his multiverse machine while letting out a soft evil cackle and flipped a switch. Generators activated and a portal took form in the machine, energy crackled and lights flickered in the room.

"YES!" Eggman declared, "Come forth, my new supervillain partner! HA HA HA HA HA!"

As if the portal were an echo chamber tunnel, a sinister cackle that sounded different from Eggman's trademark laughs made its way into the lab and echoed off the walls. Footsteps followed suit and a tall figure approached, coming closer and closer as the seconds passed.

Eggman watched with a vile sneer while his lackeys trembled, the figure came closer and soon stepped out of the portal and into the very universe he was entering.

Now he could be seen a lot clearly; A milky-white face, orange eyes and green hair, clad in a purple suit. This man was human, but nothing like anyone had seen before. He looked like somebody who bathed in a pool of toxins that altered his appearance; This was The Joker.

Eggman's portal machine deactivated and Joker took in the world around him while Eggman observed him. Joker looked at the mad doctor and let out another creepy laugh.

"My, my..." The Joker said, "This is quite the gag, I thought I'd never see the day when I'd enter a new universe to take in the hilarious sight of a muscular Teddy Roosevelt in a military uniform with colorful robots in an evil scientist's laboratory."

"Hey!" Cubot protested.

Eggman ignored his lackey and focused on Joker as he smiled in a welcoming manner, "Welcome, my new friend. I look forward to working with you to finally defeat that muskrat known as Sonic the Hedgehog, if you're interested in a partnership."

The Joker just chuckled, "An evil partnership with you? Oh, Teddy, you are such a moron if you think we would make excellent partners. This world is so perfect for me to terrorize without Batman to even try to stop me."

Upon hearing the insult, Eggman became very angry. "HOW DARE YOU INSULT ME, YOU WACKY IDIOT?!" He shouted, "I OUGHTA HAVE YOU BOOTED BACK TO THE DIMENSION FROM WHICH YOU CAME, NOBODY MOCKS THE GREAT DOCTOR EGGMAN, NO ONE!"

Eggman approached the green-haired lunatic with a raised fist and tried to punch him in the face, only for Joker to duck and avoid the strike before pushing Eggman backwards.

The doctor reached for a spare laser gun, but The Joker drew a remote-looking device and pressed a red button that caused the gun to spark and disintegrate instantly. Joker's tool was an electro-disabler, a device that prevented advanced tech from working.

A furious Eggman glared at his would-be ally and shook his fist again. "NOW THAT'S A CHEATING TACTIC, YOU NO GOOD GREEN-HAIRED LOSER!" He yelled.

Joker lagged his index finger in a taunting and lecturing manner. "Ah-ah-ah. Manners, Mr. Eggman." The Joker said with a vile smirk, "Now here's a little 'joke' from Mr. Joker; What do you get when you cross an insane mastermind with a gun? Ha ha ha! I'll tell you, THIS!"

The Joker drew a gun from his pocket, pointed it at Eggman's head and pulled the trigger. Eggman felt the "bullet" hit him in the head and nearly lost his balance in the process.

Orbot and Cubot panicked, worried that the attack may have been fatal. The bullet fell to the floor and Eggman groaned, "Ugh, I can't believe you shot me, you menace."

"Don't be such a complainer." Joker sneered, "I nailed you with a fake bullet, which still hurt anyway. But now that I've taught you 'a lesson', this lair and your precious robots shall belong to me." He reached into his pocket, "Now where is that...? Ah, there it is."

Joker pulled out another remote control-looking device from his pocket and put away his gun. The device had an antenna, a skull symbol and a pair of menacing purple buttons on it.

"Behold the Joker-nator!" Joker boldly declared, "With this device, I can unleash Joker gas, Joker-ize your robots and turn your fortress into my new lair. First order of business, GET RID OF YOU AND YOUR ROBOTS! HA HA HA HA HA HA!"

Eggman was about to protest when Joker pressed a button, causing a loud blip sound. Seconds later, a field of energy surrounded both the mad doctor and Orbot & Cubot...

On Bygone Island, Sonic and Knuckles were playing volleyball with Amy and Sticks by the beach, minding their own business with no Eggman attacks to worry about. It had been ages since the vile scientist last attacked and today was the perfect day to relax. Unfortunately, unbeknownst to them, their well-deserved peace was about to be short-lived.

A massive bright light flashed and Doctor Eggman appeared out of thin-air with Orbot and Cubot. The mad doctor landed flat on his back upon the ground while Orbot and Cubot got their heads stuck in the sand.

The appearance of Eggman and his lackeys completely surprised Sonic and crew, having not expected to see their arch-nemesis appear.

Judging by the fact they'd seemingly just been transported here without the usual Egg tech, something ominous was afoot. Shrugging off their confusion, the team ran over and helped Eggman up while digging his two robots out of the sand.

"Ya gonna tell us, what's goin' on, Eggy?" Sonic asked in his usual demeanor, "Hopefully this isn't a ploy or that crazy viral goon Nominatus just made another comeback."

"As if my day couldn't get worse..." Eggman grunted, "I'm in the custody of my arch-enemies, which is actually a relief given the crisis involving that creep clown."

Right on cue, a swarm of Bee-Bots, Moto-Bugs and Crab-Bots arrived on the beach, sporting a purple and green paint color with menacing purple eyes. And to top it all off, the Egg Mobile flew over with its pilot being none other than a green-haired man with a milky-white face.

"My devious greetings to you all!" The Joker cackled, "Its been quite a bit since we last met, Doctor Eggman. As you can see and probably fear, I just conquered your lair and altered your robots."

Upon seeing Joker with his own eyes, Sonic got into a heroic combat stance even as he glanced at the robots and the creep in the Egg Mobile. "So, you're that clown-faced creep Eggman was talking about." Sonic quipped, "If you're so confident that you'll conquer the village and the rest of the island, you're out of line since you're gonna have to get through us."

Joker hissed gleefully, "Oh really, do you and your little league think you can defeat me, hedgehog? We'll see for sure, now enough boring chit-chat. Joker-niks, ATTACK!"

The Joker-corrupted Eggman Badniks moved forward, ready for battle. Eggman ran for it while the Sonic gang prepared to fight, Amy drew her hammer and Knuckles balled up his fists. Bee Bots flew in and fired purple laser beams, Sonic leaped into the air and launched a homing attack on a Crab-Bot that sported a Joker face on its back, trashing it without a sweat.

Amy lunged towards the nearest group of Jokerized Badniks and brought down her hammer on a Jokerized Moto-Bug and a trio of Crab Bots. The pink hedgehog twirled her weapon and said confidently, "Never mess with a rose even if it doesn't have thorns."

Knuckles grabbed a Mantis Bot and smashed it into a Crab Bot. Afterwards, Knuckles threw away the robot and remarked with a sly smirk, "Puny robots." Many more Badniks entered the fray, summoned by their corrupting master. A purple-green version of Burnbot rolled in and advanced on Sonic, clicking its claws until the hedgehog smashed him to pieces.

Sticks let out a shrill battle cry and attacked a horde of Badniks with her bo-staff, smashing them all. Then she deployed her trademark boomerang and kicked apart a Mantis-Bot.

At one point, Eggman had enough of being on the sidelines and joined the fray. He stomped on a Crab-Bot, kicked a Moto-Bug away and punched apart a Bee-Bot's face. Eggman howled like a very angry gorilla, challenging The Joker and his own robots. Orbot and Cubot huddled together, trembling in terror at the sight of their master going to town on his own robots.

Up above in the "Joker Mobile", Joker observed the battle with a cold smirk on his face. He didn't even care about the outcome, especially as long as he prevailed.

"If those fools really think they can defeat me, they've yet to deal with my secret weapon." Joker cackled, "It's time to make some laughs." The maniac piloted the Egg Mobile over the perimeter and stopped just above the Sonic-Eggman gang, ready to put his plan into action.

Joker pressed a large green button on the mobile's dashboard and the vehicle's underside opened up, bomber-style. A large green canister dropped out and landed on the ground, exploding into a large cloud of green mist, clouding the senses of Sonic, Eggman and the others except for Orbot and Cubot.

One-by-one, the corrupted Badniks pulled back and Sonic looked around with mild confusion. Then he felt ticklish and started giggling, the giggling became a fit of laughter and Sonic fell over while laughing like mad.

Knuckles became a victim of this laughing phenomenon too. As the red echidna observed Sonic's strange behavior, something tickled Knuckles and he began laughing like crazy too.

It didn't take long for Amy and Sticks to become victims of the gas that made people laugh too. Amy giggled first, followed by Sticks. Both girls fell over with tears forming in their eyes as the BFFS let out a shriek of laughter. Team Sonic had become victims of laughter-causing gas. Eggman fell victim too, collapsing to the ground as he let out a stream of evil laughter.

This was The Joker's secret weapon up his sleeve. Joker had deployed it in his world many times, now he was using it on Sonic and his crew in this world.

Joker flew down in his Joker Mobile to look at Sonic, who kept laughing and rolling around on the ground. The green-haired menace pulled out a camera, ready to snap a photo... until the world froze around him and time came to a standstill.

Something struck the Egg Mobile so hard, the flying machine crashed into the ground and Joker tumbled out. He got back up, gritting his teeth with fury as he looked for his lost camera.

A foot kicked Joker in the head so hard, he fell flat on his back as his eyesight became fuzzy very quickly. A bright light flashed and Shadow the Hedgehog stood above The Joker, glaring at him with clenched fists. "How did you like that, you pathetic clown?" Shadow asked coldly.

Joker drew a gun and pointed it at Shadow, but the Ultimate Life Form kicked it away. He grabbed Joker by the neck, pulled him up and punched him in the face. Shadow threw the deviant into the air, teleported upwards and kicked him into the ground. He let loose, beating up Joker like he was nothing. Then he booted him in the head, giving Joker a hard concussion.

Unable to take the pain, The Joker passed out. Shadow whipped out a remote-control device and pressed a button, creating a space-time portal from thin air.

"Don't ever come back here to this universe!" Shadow growled to the incapacitated Joker. With that, he threw him into the portal and pressed the button on the warp generator. Just like that, the portal closed and Joker was defeated.

With the enemy taken care of, Shadow snapped his fingers and the laughing gas vanished. Another finger snap later and time returned to normal along with Sonic and the others.

"Ugh, what the heck just happened?" Sonic remarked as he regained his senses, he looked up to see Shadow as confusion rolled over him, "What the what? Shadow? What are you doing here? This is not expected, even though your appearance is often unexpected."

"I was helping you get rid of that creep's pathetic face." Shadow replied fiercely, "You should be thankful for now. We'll meet again, Sonic. But next time, on my terms."

Shadow teleported away and Sonic just shrugged at the Fourth Wall with a smile before fist bumping Knuckles as Amy and Sticks hugged each other with relief. Eggman had Orbot and Cubot gather up as many broken robot parts as possible while he made some repairs on the Egg Mobile. Luckily, Eggman's remaining robots were back to normal and heading back to the lair.

"I know we ended up getting help from Shadow on the brink of defeat..." Amy commented, "But at least we get a happy ending with The Joker defeated." She looked at Sticks and the girls nodded in agreement, knowing they could move on to other adventures and misadventures.

Eggman finished repairing the Egg Mobile and started up its engines as Orbot and Cubot joined him. "I'll see you again next week, losers!" The doctor called out. The blue hedgehog and the crew nodded in agreement, always ready for anything. With that, Eggman flew back to his lair to relax and take a little break from evil for now.

The End