The Talent Show had devolved into a sensory nightmare. SpongeBob's high note was still echoing through the mall, causing Lord Beerus to cover his ears and Simon Cowell to actually contemplate a career change to competitive knitting.
"Enough with the singing!" Thanos roared, finally ripping himself out of the brick wall. He looked at his hand. "Where... where are my stones?!"
"Oh, you mean these?" Deadpool asked, juggling the Infinity Stones like they were cheap marbles. "I traded them to Bugs Bunny for a 'Get Out of Jail Free' card and a literal ACME anvil. Speaking of which..."
Deadpool pointed up. A 10-ton anvil was currently hovering over Thanos's head, held up by a single, thin piece of dental floss.
The Mecha-Mashup
"If we can't win with music, we win with hardware!" Tony Stark shouted. He tapped his chest piece. "Jarvis! Initiate the 'Everything and the Kitchen Sink' protocol!"
"On it, Mr. Stark," a voice echoed.
Suddenly, Genos's arms detached and flew toward Tony. The Power Rangers' Dinozords came crashing through the glass roof, and Optimus Prime drove into the food court, transforming mid-drift.
"Autobots! Assemble... this weirdly specific robot!" Optimus commanded.
In a flurry of sparks and copyright-infringing metal, the Multiverse Megazord was born. It had Iron Man's head, Optimus Prime's torso, Megazord legs, and for some reason, Voltron's flaming sword.
"Target acquired," the Megazord's voice boomed (it sounded like a mix of Peter Cullen and a toaster). It pointed its finger at a tiny speck on the floor.
It was Plankton. But he wasn't alone. He was piloting a giant, robotic version of SpongeBob made entirely out of stolen Krabby Patty grease.
The Romantic Complication
While the giant robots were squaring off, Rentarou was busy being the world's most intense boyfriend. He was currently shielding Shizuka from a stray piece of flying rebar.
"Are you hurt, Shizuka-chan?!" Rentarou asked, his eyes burning with protective fire.
"I-I'm okay," she whispered through her phone app.
Suddenly, a golden lasso snared Rentarou's waist. He was yanked backward into the arms of Wonder Woman (Diana Prince).
"Such bravery," Diana said, looking into Rentarou's soul. "I have seen the warriors of Themyscira, but none possess a heart as... crowded as yours. You fight for love with the intensity of Ares himself. I must have you in my Justice League."
Karane and Hakari appeared instantly, their faces twisted into masks of pure "Oh-No-You-Didn't."
"EY! GOLDEN GIRL!" Karane barked, her pigtails vibrating with rage. "Let go of him before I punch that tiara into the next DC reboot! He's ours! All 27+ of us!"
"A harem?" Wonder Woman tilted her head, confused. "Is this an Amazonian custom I was unaware of?"
"It's a Rentarou custom!" Deadpool interjected, popping up between them with a bucket of popcorn. "And honestly, Diana, you'd fit right in. You've got the hair, the tragic backstory, and the ability to fly. That's like, three 'Girlfriend Archetypes' in one!"
The Climax of the Madness
The Megazord swung its sword. Plankton's grease-bot fired a mustard laser. Saitama was just trying to find a microwave for his cabbage.
"I've had enough of this mall!" Saitama sighed. He looked at the giant robots, the goddess, the spy, and the rabbit. "I'm ending this. Serious Series: Serious Exit Strategy."
Saitama didn't punch anyone. He simply walked toward the front doors of the mall. But because he was walking with "Serious Intent," the friction of his footsteps began to undo the reality of the crossover.
The Marvel characters started turning back into comic book sketches. SpongeBob started drying out. Bugs Bunny checked his watch and realized his contract was up.
"Wait!" Deadpool grabbed Soum's name from the bottom of the screen. "We can't end it yet! We haven't even seen Goku eat the entire food court!"