As it all started the summer came as it was the hottest temperature so much that at Nascita Ravel, Akeno, and Misora were already burning up as Akira and Sento were driving around town

Sento: "Where are the others?"

Ravel: "Oh my goodness it's so freakin hot."

Akeno: "I agree." Then she drinks ice water as the news started

Misora: "Ryu is visiting his parent's grave while Ryuga went off to do something." Then a meanwhile short moment of Ryu placing flowers on his parents grave "Azazel and Gentoku... well" Another short moment where Azazel is already drunk and as Gentoku was asleep with three fans blowing at him "And Saji and Kazumi they went to pay respects to the trio." Then a third short moment where Saji and Kazumi payed their respects to the Hokuto Trio

Sento: He sighs "Great it looks like there are only two Kamen Riders doing something."

Akira: "Dad expect nothing some of us have our own lives but for now it's best to calm down. I think the heats getting to you." Then Sento increases the speed

Meanwhile

As armed security appears surrounding a van as a bunch of people are a bit back away from the security

News reporter: "And this comes in that- oh wait the new prime minister of Touto comes up to make his speech." Then the new prime minister of Touto Ino Kengo approaches the stand as he gives his speech

Kengo: "Citizens today we have come here as once was a split country but today I will make sure that this problem won't happen again!" The audience cheered

Then a short comments of each of the other prime ministers from Seito and Hokuto

Mitsuomi: "Here in Sieto I, Gohara Mitsuomi..."

Ryoka: "Here in Hokuto I, Saiga Ryoka will do my duties as governor."

Kengo: "The three countries will agree to work together. It'll be a new chapter for Japan!" Then everyone cheered

Then  meanwhile as Sento droves as he protects a kid that was about to get killed by some smash clones

Akira: "Ok that hunch was just a hunch." Then he went up to the young kid "Are you alright?"

Young kid: "Who are you two?"

Akira: "That isn't important right now. You should get going as things will get ugly if you stick around."

Young kid: "Yeah!" Then he ran off with his sister as Akira and Sento faces off the two smash clones

Akira & Sento: Akira pulls out the standard rabbit and tank bottle as Sento pulled out artificial versions of the bottles "Now shall we begin the experiment." They twist the cap of the bottle and insert them onto their drivers

Rabbit! Tank! Best match

Then the two this the crank as pipes with two colors appears making the shape of half an armor

Are you ready!

Akira & Sento: "Henshin!" Then the two half armors merged into one

Hagane no Moonsault! RabbitTank! Yeahhh!

Kengo: "Now there is something I must tell everyone this question. Do we need Kamen Riders? They were the ones who started out the war against the countries." Then Ryu and Ryuga were given a ride "But Build is by far the worst as he backstabbed his own country and yet continues to fight. Should we even let him run loose as he could destroy this country?!" Then the audience cheered for what Igo said as they all said

Audience:"Destroy! Destroy! Destroy! Destroy!"

Kengo: "Today we shall destroy build!" Ryu and Ryuga watched the news and saw what was happening while Igo used somehow mind control everyone that was around him and those people distrust as Akira and Sento were in TankTank form defeating the last smash clones

Sento: "Oh no..."

Akira: "What's wrong?"

Sento: "Run..."

Akira: "Why?" Then Sento pointed a crowd of people coming towards them as the two booked it and ran for their lives but people were after them "WHAT THE HELL IS GOING ON?!"

Sento: "WAIT A MINUTE IT'S THE MIDDLE OF THE SUMMER AND YET EVERYON- oh no..."

Akira: "DAD JUST TELL ME WHAT THE ACTUAL HELL IS GOING ON?!"

Sento: "I remember this, I got chased by every people which was caused by- Igo."

Akira: "WAIT HOW?!"

Sento: "ALRIGHT IT'S TIME FOR SOME HISTORY YOU SEE EVOLTO AND THE OTHER THREE PRIME MINISTER AREN'T HUMAN BUT A RACE KNOWN AS THE BLOOD TRIBE. LONG STORY SHORT THEY WANT TO DESTROY THIS COUNTRY AND THE WORLD!!"

Akira: "QUICK WHERE DO WE GO NOW?!"

Sento: "FOR NOW WE JUST RUN!!!" The two kept running and dodging any people who are after them as a helicopter fired at them

Akira: "THIS IS CRAZY!!!" Then a... person was launched like if he was a missile "WHAT THE FUDGE!!!" Then he helicopter exploded as Sento was on the bike as well as Akira hopping on as the two are in RabbitTank form as Akira was shot off the bike

Sento: "SON!"

Akira: "Don't worry!" Then he pulls out a button and pressed it and then Ryu's bike appeared to him "Sorry Ryu but I promise not to get a dent on this!" He hops on and drives as the two were close as the bridge was about to open up and then the two escaped from the crazy mobs

Sento: "Phew.... wait isn't that your friends bike?"

Akira: "Trust me he'll never know."

Meanwhile Ryu sneezed

Ryuga: "Hey you alright?"

Ryu: "I don't know why but I felt like someone is touching my bike. Maybe i'm going crazy."

Back to the chase

Akira and Sento ran on foot at a soccer field where soccer players were after them and the two hopped to the stand where the audience could see the game

Akira: "Oh god... This is so tiresome." Then Saji, Kazumi, Azazel, and Gentoku were there

Saji: "Well then you two can you explain how this all started?" Akira got shocked about him but explained everything "Oh that's why."

Akira: "Yeah now if you need us me and my dad will continue to run."

Gentoku: "You should everyone is after you two." Then he inserts his crocodile crack bottle onto his driver

Crocodile!

Robot jelly!

Azazel, Kazumi, Saji, and Azazel: "Henshin."

Tsubureru! Nagareru! Afurederu! Robot in Grease! Buraa!

Wareru! Kuwareru! Kudakechiru! Crocodile in Rogue! Oraa!

Then the two hold off against the audience as the two continue driving inside of an empty mall as people are still after them while the others were holding off against the people without hurting them as cheerleader were repeatedly kept saying destroy the prime minister of Touto appeared

Ryoka: "Oh look the Kamen Riders are trying to hold off while Build is escaping how adorable."

Gentoku: "Great her...?"

Ryoka then pull out the scissors lost bottle as she becomes the scissors smash as big scissors were launched at the four as they were on the ground as the people grabbed their robot jelly and the bottles causing their armor to disappear and for the four to be pinned down

Ryoka: "You can run but you can't hide Build."

Then helicopters were searching for Akira and Sento as the two were hiding behind a trash as Sento watches the news and then they hear barking from two dogs

Sento: "Aww so cute. I gotta..."

Akira: "Dad no."

Sento: "Come on it's just a picture." Then he took a selfie with the dogs and then the dogs runs back to a crowd of people who saw what just happened and they chase them and Akira and Sento ran

Akira: "OK DAD WHEN THIS IS OVER YOUR GETTING A KICK TO THE FACE!!!"

Sento: "THEY WERE CUTE!!!"

Akira: "YOU'RE AN IDIOT DAD!!!" Then the two made it to Nascita however Ravel, Akeno, and Misora are already mind controlled and then Akira pulled a knockout blow on the three

Sento: "Ok that was uncalled for."

Akira: "Yeah it was uncalled for when they can beat us up." Then he got a call from Ryu "Hey."

Ryu: "Yo dude what's going on?" Then he explains everything "Wait what do you-" Then suddenly Mitsuomi was in the car with the two

Mitsuomi: "Yeah sorry but that won't happen." Then Ryu knockout the driver causing for a complete stop as Ryu, Ryuga, and Mitsuomi steps out of the car "Now then." He pulls out the zebra lost bottle and then becomes this abomination

Then Ryuga and Ryu pulls out their drivers and Ryu uses the magma knuckles and Ryuga uses his own magma knuckles as well (A/N: Ryuga has his own magma knuckles as well so don't bicker me)

Bottle burn!

Cross-Z Magma!

They both twist the crank

Are you ready!

Ryu & Ryuga: "Henshin!"

Gokunetsu kinniku! Cross-Z Magma! Achachachachachacha Acha!"

Then the two go hand to hand against the zebra as this was to by time as Kengo appears and the first thing he did was mind control Ryu and round house kick Ryuga out of here causing him to be knocked out and then Kengo and Ryu take thier leave

Meanwhile

Sento and Akira were back at Nascita and the two were driving away from people again and this time to stop them from going further Sento threw a bomb at the car and before Akira knew it the car exploded causing the people to stop

Akira: "THAT'S TWO DAD!!!"

Timeskip

The two made it to a place where they thought nobody could find them

Akira: "Ok dad explain everything now before I'll roundhouse kick you."

Sento: "Ok. Let's see the three prime minister work with Evolto so long story short you'll go and kill them."

Akira: "Question. How?"

Sento: "Well That-" The Kengo appeared with guards and one controlled Ryu

Akira: "Oh crap Ryu!"

Kengo: "Well well looks like Build is caught now then you'll surrender to us and give us the Pandora Box." Then Ryu transforms into Great Cross-Z Dragon and then Sento transforms to HawkGatling and Akira into KirinCyclone

Akira: "Ok were screwed we gotta run."

Kengo: "There is nowhere to run. Everyone in this nation is your enemy."

Akira: He mutters "Except hell." Then Sento and Akira fight Ryu and the two transforms into Rabbitrabbit form until Ryu defeated Akira and Sento with no mercy and then it suddenly rained as Ryu then grabbed his hazard trigger

Kengo: "Well done." Then Ryu handed him his driver with the great cross-z and the hazard

Akira: "No..." Then he attempts to stop him only Ryu to kick him in the face and placed his foot on his head "Gah..."

Kengo: "Now then." He puts on the driver and the hazard trigger

Max Hazard on!

Great Cross-Z Dragon!

Kengo: "Henshin!" Then he twist the crank and then Ryoka, Mitsuomi, and Ryu fusiles with Kengo to form a greater foe

Kengo: "Sento and Akira Kiryu let me end the both of you." Then he shot fire at the two of them until a black hole absorbed it only to find out it was Evolto helping them "Evolto what are you doing?"

Evolto: "Yo were just after the hazard trigger that's one thing but killing these two is taking the cake." Then the three disappears

Timeskip

It was night and the three were at a harbor on a boat and still raining as Akira wakes up from his beating as Evolto was already waiting

Akira: "Why the hell did you save us?"

Evolto: "Don't think of it. I only did it because I felt like it plus he was using you to grab the hazard trigger. In the end all you were is just a puppet that fell into his hands. A hero with its ideology hollow-"

Akira: "Shut up!" Then he gets out of the board

Sento: "Wait!" He follow him. As Akira got so angry that he knocked out a couple of trash and then Akira got a call

Akira: "Hello..."

Kengo; "If you want Ryu back then you must bring the Pandora Box to the location of my choosing." Then Akira hangs up

Katsuragi: "Don't tell me your gonna listen to what he said."

Akira: "..."

Katsuragi: "Well then what would happen if the rider system never existed. Than there would be no war."

Akira: "If it didn't exist than I would be dead by that fallen angel." Then he started having flashback on his fight against Raynare "Plus even if I didn't died then I wouldn't known those that I cared. I get it now the key for earth survival was within Ryu..."

Katsuragi: "Are you an idiot?! He was made for destruction!"

Akira: "You're wrong. He may be an idiot someone who fights first ask question later but... he's my friend."

Katsuragi: "You're just an idiot..."

Akira: "I gotta get somewhere without rain." Then he went walking back to Nascita

Meanwhile

With Saji, Kazumi, Gentoku, and Azazel they were trying to get out but it took a long time

Saji: "Hey keep me steady-" Then he fell "Gah. Why the hell am I doing this?!" Then the four argues for a bit until Utsumi appears above them

Utsumi: "Trying to get up? Well I can help but you must beg."

Saji; "Wait why would we-"

Gentoku & Azazel: "Please let is out!" The two were begging as Saji and Kazumi facepalms

The next day

Akira came to where Kengo wanted him to meet with the box

Akira: "Alright I'm here now return Ryu and it'll be all over-ish."

Kengo: "Unfortunately that won't be possible but how about we settle it in a battle."

Max hazard on!

Then Ryoka and Mitsuomi transforms

Great Cross-Z Dragon!

Then he twist the crank

Are you ready!

Kengo: "Henshin!"

Then Akira does the same as he pulls out his driver and his Genius Bottle

Overflow! Wake up Cross-Z! Get Great Dragon! Buraburaburabura Bura~h! Yabei!

Great! All yeah! Genius!

Then he twist the crank

Are you ready

Akira: "Henshin!"

Kanzen Muketsu no Bottle Yarō! Build Genius! Sugei! Monosugei!

Then the two started fighting as their speed and strength were close to being matched but Kengo had the upper hand

Audience: "Destroy! Destroy! Destroy! Destroy!..."

Kengo: "Look at that everyone wants to see you dead it's funny really your not a hero just a nobody."

Akira: "Shut up! I don't care if everyone hates me. Or if everyone wanted to kill me. As long as I live I'll keep on fighting!" Then he rabbit bottle turned gold "Huh? Ryu... I'll take your life even if it kills me." Then he summons his Fullbottle buster and insert the rabbit bottle onto the Fullbottle buster

Rabbit!

Then Kengo commands the people to attack Akira but he moved fast enough to dodge them and for him to deal the blow causing Ryu to separate from Kengo and Akira grabbed his arm from falling but Kengo blast Akira but Akira protected him by using his back to block the attack but was launched a bit far as his armor disappears

Kengo: "Touching But your too late." The hazard trigger was inside the box and it created a powerful energy that created a sphere "I'll be able to destroy this world with this power!" Then Kengo was surrounded in a sphere as it dived deep in the core of the earth

Akira: "Ryu!" Ryu got up

Ryu: "Ugh what happened?" He finds himself holding the dragon bottle but it was silver instead of blue "Wait then-"

Ryoka: "Build. Time for a game."

Mitsuomi: "This is perfect as I'll be able to kill these brats."

Saji: "Hey guys we'll take over from here." Then he Gentoku, Azazel, Kazumi, Sento, and Ryuga appears as they transforms

Robot jelly!

Crocodile!

Great! All yeah! Genius!

Bottle burn! Cross-Z Magma!

Saji, Gentoku, Azazel, Kazumi, Sento, and Ryuga: "Henshin!"

Kanzen Muketsu no Bottle Yarō! Build Genius! Sugei! Monosugei!

Wareru! Kuwareru! Kudakechiru!  Crocodile in Rogue! Oraa!

Gokunetsu kinniku! Cross-Z Magma! Achachachachachacha Acha!"

Tsubureru! Nagareru! Afurederu! Robot in Grease! Buraa!

Then Sento, Gentoku, and Saji went to attack Ryoka as Azazel, Ryuga, and Kazumi go after Mitsuomi

Akira: He grabs the dragon bottle "Hmm."

Ryu: "What is it? You know those two aren't a best match."

Akira: "I wouldn't count on it." Then a barrier appears around then Vernage, Ravel, and Akeno helped carrying her

Vernage: "You two will bring hope." Then she used her powers to fuse the Genius Bottle, the rabbit and dragon bottle to form a new bottle

Akira: He grabs it "Now lets begin the final
experiment." Then he gives it a shakes as equation appears around them as he inserts it into his driver

Cross-Z Build!

Then Akira twist the crank and Ryu was about to leave but he can't

Ryu: "Umm dude I'm trap!"

Are you ready!

Ryu: "No!"

Akira: "Henshin!" Then the two fused into one

Rabbit! Dragon! Be the one! Cross-Z Build! Yeahhh! Yeahhh!

Then a few seconds of quietness

Ryu: "Eh?! Did we just fused?!"

Akira: "I don't get it but screw that we broke the laws of physics! But for now we should deal with Kengo!"

Ryu: "Yeah!" Then they both went inside the hole that was going down to the core and started fighting Kengo as the others were fighting Ryoka and Mitsuomi and defeating them for good

Kengo: "No matter what everyone won't appreciate you or your efforts!" Then the two collided with one another

Akira & Ryu: "That's not what we fight for. We fight for peace and love!" Then they kicked him in the face as Akira twist the crank as a golden rabbit appeared and the two landed on it and goes for a kick on Kengo as the three were sent back up to the ground

Kengo: "Impossible two humans can't beat me!" Then a dragon made out of energy appeared as they were still getting shot up into the air

Akira & Ryu: "I get the feeling we can't loose! The formula for victory have been set!"

Are you ready!

Then a helix out of gold and silver energy traps Kengo

Akira & Ryu: "Love and Peace finish!" Then they kicked him to the ground as the two were not looking back as Kengo exploded and was gone for good

Evolto: "You guys failed me." He was referring to Kengo and other two

Timeskip

Akira and Ryu were back to normal as the Genius bottle and the rabbit and dragon bottle were back to the way they were

Akira: "Well I guess it was only a one time form. Good thing i'm not fused with you again."

Ryu: "Me too."

Akira: "Get your own thoughts."

Ryu: "Screw you!"

Akira: "No thanks I don't swing the other way." Then the two laughs as they do a bro fist

The next day

Everyone were hanging out as usual

Akira: "Well that was over for now..."

Saji: "Yeah but there's still Evolto."

Ryu: "As long as we have hope we can survive."

Timeskip

Akira was inserting the password 'Love and Peace' which worked and got more information on hazard level 7 and then the white panel shot a energy blast which sent Akira to see Kamen Riders fighting monsters

Akira: "What the hell is going on?!" Then suddenly a mech appears as a new Kamen Rider appears

???: "Hey you should get out of here."

Akira: "Huh? 'Kamen Rider'."

???: "That's right my name is Kamen Rider Zi-O i'm told that i'm the evil overlord but I don't by it." Then he pulls out a watch

Build!

Then he insert it onto his driver

Rider time! Kamen Rider Zi-O! Armor time! Best match! Build!

Then Zi-O takes care of dealing with the monster as Akira was back at the lab

Akira: "What the?! Was it all a dream?" He kept thinking on about it

The end