Spoilers from included and/or represented works abound. Please read this fiction carefully.
"Lucy!?" David is shocked to see the Akasha Terminal used. "You're being..."
"You impede my enjoyment, and that disappoints me." Lucy replied.
"Die!!!" Smasher tried to activate Sandevistan.
But Lucy manages to hack him, breaking the full cyborg boogeyman. He explodes, much to everyone else's shock.
"Turns out your auto-counter software has expired nowadays." Lucy then laughed.
"So that's why the V managed to hack the man-turned machine and busted him with that in his previous life?" Zanza asked.
"How do you know?" Lucy asked back.
"Spark off!" Six people shouted.
"Noah, Mio, Lanz, Sena, Eunie and Taion, we have problems!" Nina reported.
"The Ouroboros has arrived!" Queen Nia declared. "We present you-"
"Shut up!" Lucy interrupted Queen Nia.
"Watch your mouth for our Queens!" Lanz responded. "We must snuff you out and take back your mind, miss!"
"Thank you." Queen Melia thanked the Ouroboros.
"Everyone, go!" Noah and Mio jumped into combat, with the rest of Ouroboros.
Lucy removed the restraining and used her monowires to attack the group. She was severely outnumbered, so she dodged and shifted their attack. She used monowires to try and cut through. However...
"Ouroboros... Interlink!" Noah and Mio Interlinked, and turned into Noah as Ouroboros.
"How could this be!?" Lucy then tried to run away. However, she gets hit by the dull side of one of the Ouroboros swords as wielded by Noah.
"This is off-limit, miss!" Mio told Lucy.
"For the Queens!" Noah declared, as the Ouroboros surrounded Lucy.
Lucy watched in fear as the rest of the Ouroboros Interlinked as well, specifically into Lanz and Taion.
"Mimi, stop this cyberpsycho netrunner!" Sena told Mio.
"I'm not cyberpsycho!" Lucy corrected Sena. Sena then facepalms internally.
"Let's me fix her." Taion then have the Mondo surrounding the Akasha Terminal, right on her left ear. This diverted the mind-controlling properties of the Akasha Terminal, and freed Lucy.
Lucy then fell down, while the group approaches her.
"Good job, the future that doesn't deserve gods." Shulk congratulates the Ouroboros.
"Wake the spark up, missy!" Eunie tried to wake Lucy up.
"Sena, good thing we came just in time." Mio complimented Sena.
Sora burns the Mondo holding the Akasha Terminal with Firaga, then used healing power on Lucy.
"Adam Smasher is screwed... Someone's gotta fix this..." David commenting on Smasher.
"Good thing is that I'm an engineer." Chizuru replied. "Unfortunately, I'm not a ripperdoc, so the cybernetics from Night City is... awkward for me to say the least."
"Where's the Night City?" David asked.
Meanwhile, SMG0 successfully freed the Seven and Lawyer Kong. The Paradigm woke up first, and her mind is fuzzy right now.
"What... happened?" The Paradigm asked.
"You're being used by Zero, but the threat of the omniverse!" Meyneth shouted for Paradigm to hear. KOS-MOS and T-elos looked at Meyneth in an awkward expression (especially with T-elos, as KOS-MOS minimally expresses herself).
"Do you really have to shout, Miss Machine-God?" T-elos told Meyneth.
One hour later...
"I hope nobody signs DMCA for the very existence of the omniverse..." Reiji said.
"Make no mistakes, the lawyer." The Foundation told Lawyer Kong. "You're a corrupt lawyer for Nintendo's policy. However, I sensed that you know something about the Zero."
"Actually, I saw that girl with white ponytail. She sued me for just existing to glorify Nintendo's stricter future for no apparent reason." Lawyer Kong explained. "This legal paradox tricked me into signing the wrong contract, and I was baited into the hand of a-"
"Netrunning girl?" The Foundation asked whether is referring to Lucy.
"Yes." Lawyer Kong confirmed. "The very existence of that Zero and that the girl's being used is... well, illegal."
"Do the Zero Point get affected by the copyright?" The Foundation touched the fourth wall, asking Lawyer Kong.
"Geez!" Gemini Sunrise, Morgan (Robin's children) and Ingrid (one of the Code Holders) are frustrated.
"Do you know about the Zero we're finding?" The Paradigm asked.
"Not much. The only things I know about her is that she registered in court and sued me there." Lawyer Kong then took out the document about the Zero. "Here, take it."
"Thanks." The Paradigm thanked Lawyer Kong.
"Document get!" The announcer declared.
"Not that announcer again..." David is uncomfortable with the voice of the announcer.
"Announcer?" Everyone suddenly got in the fourth wall. "What!?"
"Well, I just heard." David responded. "Let's go."
That evening, at Ouma HQ...
"Where am I?" Eureka, cured and freed.
"You're at Ouma HQ." Due Flabellum answered. "Welcome to the broken Endless Frontier."
"Is this..." Eureka is surprised. "Another world? And what have I done..."
"Rigna used the Getter Rays to turn you into a humanoid monster." Alfimi, the humanoid Einst, responded. "You then wreaked havoc in various worlds."
"Finally! Eureka Thurston is cured!" The scientists celebrated.
"Where's Renton?" Eureka remembers Renton Thurston. "I have to-"
"Take a break. Don't go yet." Due told Eureka. "You haven't fully recovered yet, you Coralian."
"Oh ok." Eureka then stopped. "Thanks for caring about me."
"We are in here and there together." Due said. "We're fighting against an omniversal threat."
"My darling, a Coralian has been cured!" Due called Meden Traore.
Meden Traore appeared, and is glad that Eureka is cured. However, Kogoro and Mii, who protected the Portalstone which Oros Phlox (the organization led by Due and Meden) stole, also appeared. The Shinra and Ouma agents - Reiji, Xiaomu, Saya and Sheath - all appeared as well.
"Good job!" Reiji congratulates the scientists. "Eureka, it's us!"
Eureka ran and hugged Reiji and Xiaomu. The rest then hugged them as well.
"We're glad you're back, Eureka!" Mii is happy.
David, the Seven, Sora and Mercurius then followed. They reported that both the Glitch Productions crystal and the Fortnite crystal - the latter has Zero Point powers - are all collected.
"And the murder drones, the UCE and the Celestials are scavenging the ruins we've encountered so far." The Paradigm reported.
"Very good, newcomers!" Meden congratulated the group.
"We saved Lucy." David reported.
Supported by Mickey Mouse and friends, Lucy approached David.
"I wanted to get back to you, so I ended up being used by that Zero." Lucy explained what happened to her. "I'm sorry, David..."
"It's okay." David confirmed Lucy. "And you've gone to the moon. I'm glad!"
"Yeah." Lucy confirmed.
"Congratulations, Miss Kushinada." Xiaomu congratulated Lucy.
"But we have to fix this cyborg." Bowser is carrying Adam Smasher. Then throwing the Smasher in the front, much to the shock.
"Uh oh." Eureka is disappointed.
"My consciousness... got lost, and I unwilling hacked this guy as a result." Lucy explained.
"Fix him." David told everyone to fix Smasher.
"Guys, we need ripperdocs to fix this kind!" Kogoro shouted.
"So loud..." Lucy then facepalmed.
The next day...
"Day 9." A man named Woz narrated. "Upon the nightmarish ruins of what remains of the City of Dreams, dragons are killing each other after taking countless lives."
"Destruction of this scale is previously unheard of in this place..." Woz knew the destruction of the Night City.
A few polices and civilians emerged from some of the ruins and started rescuing the trapped peoples.
An young man appeared behind Woz.
"Woz, I don't even know this world." The man have no idea. "What's this world?"
"My king, you're in Night City." Woz revealed to the man.
"How!? This world isn't just strange, it's in ruins!" The man complained.
"Zi-O!" Another man appeared. "What the hell is this?"
"We're in year 2077." Woz explained both men. "However..."
"There's no Kamen Rider." Sougo Tokiwa replied.
"Exactly." Woz confirmed. "And cybernetics seems to be prevalent to this city."
"Sounds very similar to Kikai in my dream..." Sougo recalls Kamen Rider Kikai.
"Geiz!" A woman appeared in front of everyone else. "We have to transform! Those dragons noticed us!"
"What!?" Geiz Myokoin. "Then we have no other choice..."
Everyone then stands side by side, uses watch-like trinket and put in a certain belt each. Then they inserts and go to transform.
"Henshin!" Everyone shouted and started transforming.
Shortly, they all turned into Kamen Riders: Zi-O, Geiz, Woz and Tsukuyomi. Afterwards, they went to slay the dragons.
The dragons tried to attack the Riders, but those could be handled. Instead, Riders resists everything the dragons threw into and easily slayed several of them just with some of the more basic fighting. And whenever they Rider Punches and Rider Kicks, more dragons get killed.
Realizing that the Riders are too strong for them, most surviving dragons flew away in fear. Dozens of stronger dragon, which can at least stand a proper fighting chance to the Riders, while several dozens of dragons were killed in the process.
"The dragons are quite weak." Geiz commented. "Most of them hardly stands a chance against Another Riders."
"Oh, well..." Tsukuyomi replied. "But look! Most of the remaining dragons are leaving!"
"Which leaves us only a handful of stronger dragons." Zi-O commented. "Which to be fair-"
Then most of the dragons that stayed, suddenly exploded, leaving some... robots. The remaining dragons then all left.
"Wait what?" Woz is confused at what just happened.
"What the hell is happening!?" Geiz is frustrated. "Zi-O, explain this!"
"Do I know you?" A mysterious voice.
"Who the fuck are you!?" Geiz profanely asked.
"I am Ultron. The Infinity Machine." Introducing Infinity Ultron. "And now, I've got some help, courtesy of Empress Zero."
"Infinity? Ultron?" Woz has no idea who Infinity Ultron is.
"With the Infinity Stones, I can destroy all lifes." Infinity Ultron explained. "That's the real peace."
"No, peace has everyone coexisting with each other harmonically anyway." Zi-O counter-argued with Infinty Ultron. "Also, how are we outside of our world?"
The robots emerged from the dragons, turned out to be Ultron Sentries... infected by newly-improved Sigma Virus. These Sentries came from Infinity Ultron. The Sentries surrounded the Riders.
"This isn't good! We're surrounded!" Tsukuyomi is frustrated.
"We're gonna be stronger ourselves!" Zi-O them discarded the normal Zi-O Ridewatch and readied the Zi-O II Ridewatch.
"Looks like it." Geiz then reached for GeizRevive Ridewatch.
Cross-trivia: TheRidewatches are pocketwatch-like devices used by the Riders inKamen Rider Zi-Othat contain the power of pastKamen Riders.
Ridewatches are armament devices designed like stopwatches that are the power sources for Ridewatch-compatible Rider Systems.
Zi-O and Geiz inserts those Ridewatches into their respective Ziku-Driver, and went to transform ("Henshin!"). They turns into Zi-O II and GeizRevive. Geiz turns to Goretsu in this case.
"Demon King! Il Salvatore! Let's do this!" Woz used Quiz Miridewatch and inserted into Beyondriver. Transforming into Futurering Quiz.
Then all the Riders fended off the Ultron Sentries. In the meantime...
"We're almost there." Chizuru announced.
"There's nothing but ruins?" Smasher asked David.
"I saw the dragons with my own eyes." David then explained everything he experience from revival to escaping with the rifts thanks to the dragon, and including seeing all crossing while falling through the rift.
"What!?" Everyone else is shocked with the experience.
A dragon flying away, about to crash the Dragonturtle MK. II. Chizuru evaded by maneuver the vehicle, narrowly avoiding the dragon and saving everyone onboard.
"Whoa!" Everyone as they dodged the dragon.
"Look, there it is!" David finally spotted the Night City. "It was destroyed by the dragons!"
As the Dragonturtle approaches, everyone eventually realized that the Ultron Sentries is attacking there. A dozen of Sentries even noticed and started attacking, which the Dragonturtle reacted by firing weapons to destroy them. This left one Ultron Sentry surviving the blast and entered the Dragonturtle.
"No!" Tron Bonne screamed as the Sentry is about to kill her in person.
David heard that, so he activated Sandevistan and approached the Sentry himself. Quickly enough, once Sandevistan deactivates, David is behind the Sentry and is pointing Lucy's pistol (which he took from Lucy after the quick activation) into its head.
"David?" Tron Bonne saw David coming. "David, save me!"
David pulls the trigger and destroyed the Sentry with a headshot, saving her. He left returned to his seat and returned the pistol to Lucy.
"Thank you, David!" Tron thanked David, but he turned to the seat. Tron had the Shinra agents throw the Sentry away, out of Dragonturtle.
Not long afterwards, the Dragonturtle MK. II landed and fired the weapons onto the nearby Sentries. The Riders saw it.
"What's this?" Geiz, as Shippu, approached the Dragonturtle.
"A weapon bus?" Zi-O approaches the Dragonturtle.
"Who're you?" David leaves the Dragonturtle.
"Who are you!?" Zi-O and Geiz flabbergasted at David's appearance.
"David Martinez from Santo." David introduced himself. "Edgerunner from Night City."
"The City of Dreams?" Woz heard David.
"Wait, how did you know it!?" David is shocked.
"Uh, lucky guess?" Woz is nervous. Tsukuyomi sighed.
"Hell gotta be kidding me..." David facepalmed.
"I'm Sougo Tokiwa." Zi-O introduced himself. "Kamen Rider Zi-O!"
"Kamen Rider Geiz. Geiz Myokoin from World of Zi-O." Geiz introduced himself. "And here's Woz and Tsukuyomi."
"Who are Kamen Rider anyways?" David asked. Everyone else heard that (even the Sentries).
"Damn, Kamen Riders basically the justice masked man..." Reiji guessed.
Geiz then took advantage of GeizRevive Shippu's speed, punching David. However, David activated Sandevistan just in time, rendering Shippu to be something more like a normal human for David. David then dodges the punch.
"How!?" Geiz is flabbergasted to see David dodge the punch.
"Sandevistan." David bluntly replied.
The Guardian of the Multiverse appeared behind the Riders, warning them:
"Look! that Infinity Ultron is back, and he has the help of others! Watch out!"
At the same time, all Sentries them flew away, much to everyone's surprised.
"Wow, I'm surprised these robots would go away instantly." Woz is surprised.
"Carter!?" Steve Rogers, as Captain America, spotted Captain Carter.
"They're approaching!" That Star Lord warned everyone.
The Earth-616 Avengers just left the Dragonturtle, and they already got warned for seemingly unknown reasons. Then, another Sideways Rift appeared...