DISCLAIMER: The following is a fan-fiction based story.Engine Sentai Go-Onger, the Super Sentai series, Kamen Rider Build, and the Kamen Rider series in general are properties of TOEI, TV-Asahi, and Ishinomori Productions. Soul Calibur is property of Project Soul and Bandai Namco.

Please support the official release of the upcoming Super Sentai V-Cinema, Engine Sentai Go-Onger: 10 YEARS GRAND PRIX.


Lap 025: Father vs. Son Confrontation [父親vs息子タイケツ/Chichioya tai Musuko Taiketsu]


(*Opening: "Be The One" by Pandora feat. Beverly from Kamen Rider Build*)

"It has been four months after the destruction of the Skywall and Pandora's Box. A new era of peace has been begun. But, when monsters from different dimensions start attacking, a new chapter of Kamen Rider Build's battles are about to unfold..."

[~Kono mama aruki-tsuzuketeru~] (Tonight again, I keep on walking)
[~Konya mo massugu hitori no ashiato tadotte~] (Down this same path when I come across a set of footprints)
[~Hateshinai dakedo kimi dake wa~] (Which never end. But you're the only one...)
[~Dokoka de matteru egao tayasazu ni~] (Waiting for me somewhere without ever losing your smile.)
[~There you will...~]

[~Be the One! (DA!) Be the One! All right!~]
[~
Ashita no chikyuu wo nagedasenai kara~] (I won't give up on the Earth's future.)
[~Be the Lights! (DA!) Be the Lights! All right!~]
[~
Tsuyoku nareru yo ai wa makenai~] (I will become strong! Love doesn't lose!)
[~Nanika wo tasuke sukutte dakishime~] (Help something, save something, hold something)
[~Kokoro ni furete todoku yo tsutaware~] (Touch my heart and get through, shout it out)
[~Be the One! Be the Lights!~]
[~
Messeeji okuru yo hibiku yo~] (Send the message, it resounds!)


[Interlude]

(*BGM: G7 Aqua Visor Standby music (looped without Build Driver standby music)*)

Hiroto: It's been four months after the destruction of Pandora's Box, the Skywall, and the defeats of Kozuki Kaguya and extraterrestrial lifeform, Evolto. The Go-Ongers escaped into the other Human World where Kamen Rider Build, aka Kiryu Sento resides. When the mysterious underground organization, Foundation X made their presence known in their home dimension, Sento, along with the Go-Ongers and the SOLGU resumed their skirmish against the Foundation. While saving Sawatari Kazumi from Foundation X, the Go-On Wings, Build, Icarus XYZ, and Type-S fight their way through the Foundation's Amazonz to save him. That's until we find out that from Katsuragi Shinobu's benefactor, Amataro Kai that the Foundation is using him to get close to the lost bottles.

Miu: Find out the rest in episode 25 of Engine Sentai Go-Onger: 10 YEARS PRELUDE feat. Kamen Rider Build.

[Interlude Ends]


After successfully rescuing Kazumi and simultaneously cleaning their escape route of Foundation X's swarm of Amazonz, just before the Sutou and Izumi siblings, Taki, Sento, and Kazumi leave. The Foundation's agent, Kai confronts them and reveals his and the Foundation's true agenda to them.

What Sento didn't realize from Kai is that the Foundation is actually using his father, Shinobu in order for Foundation X to steal the Lost Bottles from him.

"What are you talking about?!", Sento raised his tone the moment Kai is about to reveal his true motives.

"Heh. We were just using him. So, we can take the Lost Bottles from him.", Kai reveals his true colors to Shinobu's son.

This revelation infuriates Sento even further.

"Are you people insane?! Don't you know how dangerous the Lost Bottles are when used together?", Sento answered back to the Foundation agent.

"Like do I care. I would not find that out for myself if I try.", Kai dismissively replies with a smug tone. "I am different from that imbecile Mogami Kaisei and his counterpart from this world. I am a man with a sense of curiosity, not unlike you simpletons."

"You won't be getting the Lost Bottles as long as we're standing in your way. Period.", Goro refutes to Amataro.

Kai takes out his Nebula Steam Gun. This time, before making his escape, he gives the Izumi and Sutou siblings, Taki and Sento one last warning.

"Consider your actions as a deathwish.", Amataro responds to Goro's statement. "The next time we see you meddle with the Foundation's affairs, we will be as relentless as ever. I hope you all understand that.", he then holds the Nebula Steam Guns trigger, and by simultaneously sweeping it horizontally and releasing the trigger, causing a stream of smoke to be fired out of the gun. The smoke envelops Kai, and subsequently disappeared after that steam dissipated.

Sento is starting to fear for his father's life, after having realized Foundation X's true agenda. Should the Foundation get their hands on the Lost Bottles will even spill more disastrous results.

Even Goro, despite his self-absorbed bravado and egocentricity, is disturbed by Amataro's scientist-like robotic personality. He outright describes the Foundation agent as a complete sociopath to the core whose motivations as a researcher borderlines avarice, god complex, and/or just for the sake of scientific and technological advancement. Granted, Goro draws the line on all those as much Sento does.

"To be honest with you guys, that guy really got me unnerved by his tone.", said Goro.

Taki added, "I also thought of the same thing. This is not the first time I have crossed such a heartless person who would go in desperate heights to lust for power. That man's eyes are unfathomably empty as as his tone sounds just like a machine. All of them are bereft of any compassion or humanity.", also pointed out the similarity between Kai and Kaguya - both of them are researchers who would go so far to lust for power. What makes this ironic that Kai used to be the benefactor for the latter when the Foundation were backing her financially at that time, until the organization cut ties with her after that scandalous reveal of her history of child abuse. Kai is implied to have draw the line on Kaguya's actions. However, despite these moral boundaries, following when Sento and the others' recent encounter with him, Kai barely has any morals within him, and those "standards" he possessed served as a mask to his true personality.

The ninja couldn't help but compare the Foundation agent as a heartless artificial intelligence disguised as a human.

Meanwhile, the four Gaiark Ministers made their presence known, as they happen to have overlooked the recent encounter earlier. And, they have saw Kai lecturing the Wings and Kamen Riders earlier.

"So, that's the human associated with Foundation X, zoyo?", asked Kitaneidas.

"It's you guys again.", Hiroto muttered at the sight of his and his teams' long-time adversaries.

"We, the Gaiark have been invading the Human World and done so many attempts to pollute that world.", said Hiramechimedes, and at the same time voicing his disdain with Amataro's personality. "But, that human in white... I've never seen a human like him this heartless."

Even the Gaiark are utterly unnerved at Amataro's callousness, especially the fact that he, along with Foundation X as a whole were responsible for the invasion of the Machine World where Speedor and the other five Engines were abducted.

"The way that Foundation guy talks barely shows any feelings ojaru.", Kegalesia also noted.

"I appreciate expressing your thoughts.", Goro replied to the Gaiark ministers, "But, mind you. You guys should be careful eavesdropping and digging too much on other people's privacy, you guys might probably wind up dead. In your case, it doesn't matter since you guys are already long dead."


Later at nascita, the whole parties are gathered as Sento brought up what Amataro said to him. Everyone are consequently shocked upon hearing that Foundation X's partnership with Sento's dad was actually a ruse, in order for the Foundation to take the Lost Bottles for themselves.

"I knew that Foundation X are focused in their own agenda.", said Goro. "To think that most of their agents are fully-functional and egotistical sociopaths."

"They were using my dad so they can take the Lost Bottles for their organization.", Sento added. "If the Lost Bottles are to fall into the wrong hands, the results will be catastrophic."

As Sento points out, should the Foundation obtain all 10 Lost Bottles, according to his dad's research about them that will lead to a phenomenon that transcends beyond the scientific laws gone horribly wrong.

So far, the Lost Bottles in Team Build's possession are Bat, Castle, Spanner, CD with a total of four. While the other six - Cobra, Fukurou, Kuwagata, Shimauma (Zebra), Hammer, and Hasami (Scissor), are in Shinobu's possession. The question is, what device activates all 10 Lost Bottles to achieve the said phenomenon?

"Any options, Sento?", Goro asked.

"I'm going to face my dad myself.", said the physicist.

The rest of Team Build appear to be against this idea. But, Sento justifies that this is between him and his father, Shinobu. Goro made no hesitation in accepting Sento's idea.

"For crying out loud man, let us fight with you!", Banjou intervenes.

"Don't butt in, dipshit!", Goro raised his tone momentarily responding to Banjou. Then, turns his attention to Sento. "Okay, though your idea facing your father might be asinine as it sounds. But, I think Sento's plan is astute."

Sento continued, "Izumi-san, I want you and your guys raid the Neo Faust base in Hokuto, that will buy you guys enough time to take the other six Lost Bottles."

"Count us in, too!", Sosuke willingly asks to join with the Riders to make sure to find the other two missing Engine Souls and the Casts.

"Ditto.", Kazumi is more willing to put his life on the line to fight for love and peace.

"If Potato is going, then I'm going too.", said Gentoku as he flashes his shirt underneath his leather jacket, written "I'm with stupid", much to everyone's annoyance.

Sento decides to bring the other four Lost Bottles with him, in hopes he could gamble at his father if he ever the latter possess any of the Go-Onger's Engine Souls and Engine Casts of their partners.

Three parties - Team Build, SOLGU, and the Go-Ongers prepare themselves for their next mission. As Sento will be on his own to find and confront his father, the combined efforts of the three parties will commence the raid of Neo Faust's hideout in Hokuto to find the other six Lost Bottles. Prime Minister Suzumura approved Goro's proposal for his forces to raid the Neo Faust base in Hokuto.


In the midst of the preparations, Aizawa, Anzu, and Reiji ran into Medusa later that evening in the carnival at Moroboshi Beach.

Despite the female Phantom's hostility with the SOLGU operatives, they don't want no harm towards her. However, by looking into Reiji, she begins to sense a similarity on the 18-year old boy. That's when he decides to ask why Medusa betrayed Foundation X, her answer, it's because she was betrayed by her superior Phantom, whom she had dedicated her loyalty to: Wiseman.

Medusa couldn't accept everything that happened in her last moments; learning that Wiseman was actually the White Wizard, both assumed by the identity who gave Soma Haruto his magical powers and also that of Inamori Mayu.

The fact that Foundation X were able to recreate Medusa, what the organization did not think through is that the Medusa they created had the memories of her, which caused the Phantom to turn against the evil organization.

"So, you turned your back against those Foundation freaks because you've realized that you yourself were being used by someone you swore loyalty to?", asked Anzu.

"Don't ask as if you understand.", Medusa bluntly answered, as she doesn't want any sympathy from any of the three. But, Reiji is more willing to do so.

"I do.", Reiji answered. "I once worked with a person who dedicated herself to end the war that ravaged this country. However, I eventually realized that Iam too being used as a means to an end."

Likewise, Reiji still remembers when he still worked as Kaguya's secretary in Elpis Corporation. At that time, he wasn't aware that Kaguya is using him take advantage of Sento and the others. That's until Evolto, who still possessed Isurugi Soichi at that time, revealed the whole truth about Kaguya. Hearing everything what Kaguya has done to her family and her true colors coming to light at Reiji's earshot caused him to fall into depression. Luckily, Goro was able to knock some senses out of the young man and gave him a purpose.

"Look, it's okay show loyalty to a person you swore to. But, you should put their trustworthiness and yours to the test. That's what aniki and Sento-san taught me since then.", said Reiji.

"Reiji-kun...", Anzu sighed, and is surprised at Reiji being able to interact with a Phantom like Medusa to convince her.

Touched by Reiji's sincerity, Medusa gives something to him: a blue chip-like object which happens to be an Engine Soul belonging to Go-On Blue.

"Is this...where did you get this?", asked Reiji.

"The less you know, the better.", Medusa replied, wasting no time replying. Either way, she reluctantly joins with them out of begrudging respect.


Two days later...

At daybreak, as Sento leaves the nascita on his own. After deploying the Machine Builder from its Build Phone form, Goro is waiting for him.

"Sento.", Goro calls him out.

"Izumi-san? What are you doing, it's still early!", the physicist replied at Goro's early, yet sudden presence.

The ZETA Tech chief throws his signature Crow and Stealth Full Bottles to Sento, asking the latter to use it if things get hairy.

"You might need these. Just in case, your dad won't know what will hit him.", Goro advised the person he looked up to and close friend.

Granted, since Shinobu, as the other Build has already analyzed most of Sento's forms. Goro thought of the idea of using a form derived from the Crow and Stealth Full Bottles for Build, something that is not yet used with Build's system. As the Crow and Stealth bottles were exclusively for the G7 system through Icarus XYZ.

Sento has already pulled these tactics before back when he faced Blood Stalk. So, he's planning to do the same to the other Build.

Sento then kickstarts his bike's engine, and after putting on his motorcycle helmet and took off.

30 minutes before sunrise, Sento arrived at the place where the Skywall Incident began, where his father, Shinobu is waiting for him.

"I assume that you brought the other four Lost Bottles.", said the Katsuragi patriarch.

"How can I forget? Just tell me, what are you planning to do?", Sento asked.

"You don't want to know. Just give me the Lost Bottles, and I will give you these.", Shinobu reveals a Foundation X briefcase containing the six Engines' Engine Casts belonging to Speedor, Buson, Bear-RV, Birca, and Gunpherd.

Sento steels himself and makes it clear, "Not if I fight for those Engine Casts from you."

"Fine then, let's settle this.", Shinobu resolves not to hold back.

As both father and son ready their Build Drivers, the battle between the two of them commences that will hold the Lost Bottles and the Engines' bodies (i.e., Engine Casts) at stake.


Engine Soul obtained: Buson

Engine Souls remaining: 4 (Buson, Birca, Gunpherd, Carrigator)

Engine Soul count:

- Engine Soul in Kamen Rider Grease's possession: 1 (Bear-RV)

- Engine Soul in New G7 Icarus's possession: 1 (Buson)

- Engine Soul in Go-On Red's possession: 5 (Speedor, Kishamoth, T-Line, K-Line, Machalcon)

- Engine Soul in Go-On Gold's possession: 2 (Toripter, Jum-bowhale)

- Engine Soul in Go-On Silver's possession: 1 (Jetras)


Author's Note:

For those watching Build's latest episodes, I've overheard about merging the two parallel worlds – that of Build and his predecessors through the white Pandora panel. I'll plan to put that once this story is near its endgame arc in a different approach since Evolto and Pandora's Box are destroyed; the alternatives are with anything to do with the Braneworlds. I assure you guys, not unlike the Metroid: Kamen Rider Generations series, ending with more than 100 chapters, I'll do whatever I can not to exceed more than 100 chapters. After 10 YEARS PRELUDE, I'll be working another story on that focuses on Taki's return to her timeline, now the merged timeline due to the continuity reboot in the Soul series that is Soulcalibur VI.

I was also shocked and to an extent, sadden upon learning that Ayuri Konno, best known as Amy Yuuzuki from Zyuden Sentai Kyoryuger, is going to retire from acting. Well, it's best we wish Ayuri-san the best in her life. The last time I've heard a tokusatsu actor retiring from show business was Rakuto Tochihara, who is best known as Asumu Adachi from Kamen Rider Hibiki, announced his retirement from acting last February 2018, and lastly Assam Asimov (an inside joke to Asumu) from Tokusou Sentai Dekaranger: 10 YEARS AFTER.

There is an underlying theme in this story carried along with the lines of Kamen Rider Build'scentral theme that take this to a whole new different level. Here, the story gives the readers the message about the darker motivations of a scientist. What motivates them? Is it their avarice? Self-importance? Do they dream of being a god because of their unrivaled knowledge? Or, do they want to further scientific advancements? Granted, we have seen so many villains in the Kamen Rider series with these aforementioned traits from the likes of Ryoma Sengoku, Tenjuro Banno, all the way to Kuroto Dan of all people; genius inventors who value themselves and their intellect above all else. This also applies to Foundation X as a whole, from Doctor Prospect, Lem Kannagi, Kaisei Mogami, and exclusively to this story, Kai Amataro. In the Foundation's case, they are an evil underground organization who engage illegal experiments behind the scenes, and having collected data starting with Gaia Memories to Core Switches and more recently, Rider Gashats. Kannagi and Mogami, being associated to that organization will go far to get power to satisfy their hunger for knowledge, power, and desires for godhood and both are willing to enslave humanity for that matter.

Also, another underlying theme as Goro pointed out to the four Gaiark ministers: it is best to avoid knowing too much of someone's (especially of their questionable activities) secrets; otherwise, you could put yourself and/or everyone you love in grave danger. In short, if you suspect the secret of a dangerous individual, you could be their potential target. The four Pollution Ministers will occasionally observe the Riders and Go-Ongers' fight, and at the same time having heard of Goro and Sento's conversation. The four could most likely jeopardize them because of their presence.