A/N: HI READER

This is my first fanfic so please give me a chance, this will probably be bad at first and get better as it continues.

Without further ado let's begin 'RWBY build a legend'.

Disclaimer: I don't own RWBY or Kamen Rider build.

READYYYYYYYY GO!

Chapter 1: ARE YOU READY?!

1st person POV FLASHBACK

My name is Baron Aldwin, and I don't remember anything.

Well that's not entirely true, I only remember the last year of my life. You see, I have amnesia so I have no memories at all before one year ago. I was found on a rainy day in an alley. I only had on a white top and trousers. As I opened my eyes, I heard a gasp and turned to find a family of three, a mother and two children. The mother's name was Eleanor. She had long blonde hair that went down her back and had green eyes. The son's name was Dante. He had black hair and blue eyes and finally, the daughter's name was Jackie. She had short blonde hair and blue eyes.

At first, Eleanor was a bit scared of me, not knowing who I was. The kids, however, came up to me asking if I was ok, my only response was "Where am I? Who am I?" After a few months I was adopted by Eleanor and was given the name Baron and I took their last name, Aldwin.

We were happy, a big happy family. Later on, I learned that the father of the family died in a war as a hero. I and my adopted siblings got along really well. Dante introduced me to his favourite show a Japanese show called 'Kamen Rider'. The one we watched at the time was called 'Ex-aid', a story about doctors and video games but this story doesn't involve that Rider. We'll get to which one that was later. Jackie was a regular anime lover but her absolute favourite was produced in America by 'Rooster Teeth' called 'RWBY' and at the time, we were only on volume 4.

But eventually the happy moments had to end. On the evening of my birthday, which was the date they found me, April/12/2017, we were just driving home during a heavy rain storm and then the accident happened.

People thought it was a faulty car or a slippery road, but I know I heard a gunshot and then, after the car crashed, I blacked out for a while, I don't know how long but a while. When I opened my eyes, I saw a scene that will haunt me my entire life.

…

…

…..

…..

They were all dead. Eleanor had a broken neck up against a tree. Dante was impaled by a broken piece of the car and Jackie was through the car window. I was in shock. The people I considered family, all gone. All the happiness I had, the only happiness I had, was gone.

Several months passed by, and I was given the house of my adopted mother. A new 'Rider' series came out called 'Kamen Rider Build', about an amnesiac named Sento Kiryu who knows nothing of his past until later in the series. I knew how he felt about losing memories. Volume 5 of 'RWBY' had also recently ended.

PRESENT

It's now late June 2018, and I'm on my way to a convention. "What kind of convention?" you may ask. Well, it's the first ever Rider convention to appear in America. You see, I made a promise at the funeral. A promise to both Dante and Jackie that I will continue to watch both of their favourite shows and tell them each story of what happens to their graves.

"Finally here" I say to myself, as I walk to the entrance. I stop to have a look at a locket I have around my neck and take a look at the picture inside and a sad smile comes to my face. "Wish you could be here guys." I close the locket and tuck it back into my shirt as I'm about to take a step and open the door. I swear I see a silvery veil as I enter and then, everything went black. I hate it when that happens!

As I wake up, I find myself lying on… grass? Why am I on grass? As I get up, I see that I'm in a forest of some kind. The trees look to be an emerald green colour, bright and lively. And then that's when I look into the sky and I see something…..odd to say the least.

"What in Sam hell is going on here?!" I yell out to no one, as I see that THE MOON IS BROKEN! "So, let's see green forest - check, broken moon - check. I only need to see some black-coloured wolves and I'm pretty sure I'd be in Remnant." I look around hoping I was wrong and sighed in relief when no beowolfs appear. Looking down to my body, it seemed that my clothes had changed. When going to the convention, I had on simple jeans and hoodie, with a top underneath. Now I have on a beige coloured trench coat, with grey jeans and black combat boots and, on my head, I felt a pair of goggles, I took them off to reveal that they had purple tinted lenses with a cross hair on the right lens. Slipping them back onto my blonde head of hair, I checked if my locket was still in my shirt. Sighing with relief that it was still there, I then started to walk, but soon tripped on something.

Looking down, I found a very large brief case with a symbol I'm all too familiar with. A gear split diagonally with a line going through it. This was the symbol of Kamen Rider build "oooooh what's this?" I knelt down to open the case and my eyes widened in surprise. Inside, was what looked to be a black belt buckle with two open spaces to insert something. To the right, there was a big gear and a turn-able crank. "Wow, the build driver, but how did it get here?" But it wasn't the only thing in there, there was also about sixty little bottles. The source of build power, the full bottles, a bigger full bottle that looked more like a can of soda that was mostly silver, with red and blue 'eyes'. This was the RabbitTank Sparkling and, finally, something that I wasn't happy to see, a small red trigger shaped object with a blue button on the top and a dial in the middle, the Hazard Trigger. The only things not in there was the Full Full Rabbit Tank bottle and Genius Bottle.

I reached and picked up the driver and felt that it wasn't plastic, but felt like metal. So did the bottles, as I ran my hand across them. As I picked up the Rabbit and Tank Full bottle, and placed both them, and the driver into my coat pockets, I heard a very unpleasant growl. Shutting the case, and picking it up, I turned to see the one thing I hoped I wouldn't run into. Emerging from the bushes, were three wolf-like creatures that had pitch black fur and bone white masks and armour. On the armour was blood red markings and to finish the creepy factor they had blood red eyes. The three slowly stalked towards me as I stepped back a bit in fear. 'What do I do? How do I get of this?' I screamed in my mind. 'There's only one thing that can save me now.'

"Oh my god what the heck is that thing?!"

I pointed behind them and waited a few moments, 'I knew that wouldn't work'. For reasons of either them being stupid, or curious, the three of them turned around to see nothing, and turned back to find me running away. They gave a growl of anger and ran after me.

'I can't believe that worked, I can't believe that worked!' I continued to run from the Grimm, brief case under arm. All I could see were trees after trees and suddenly, I tripped on a rock, dropping the case and skidding across the wet grass.

As I push myself up, I see the beowolfs stop running and got between me and the case, slowly stalking me again.

"Damn it I didn't want to die like this, there has to be way to fight these things!"

I thought I was a goner until I heard a voice in my head, and no, I'm not crazy, but the voice did sound familiar.

"The driver! Use the driver!"

"What?"

"Use it with the bottles and transform into build."

"Is that even possible?"

"Would a genius physicist lie to anyone?"

Sighing, I reached into my pocket and pulled out the driver and bottles. "Here goes nothing I guess." I placed the driver to my waist and a yellow belt strap wrapped around my waist.

BUILD DRIVER

My eyes were wide with excitement and shock.

"No way." A smile stretched across my face as I held a full bottle in each hand. As I looked at the Grimm approach me, I said the line that any build fan would know.

"Now shall we begin the experiment?"

(Insert build opening theme: Be the one)

As I started shaking the bottles, the Grimm tilted their heads in confusion as to what I was doing. When I stopped shaking the bottles, I twisted both the caps on them and placed the red one, which had a picture of a rabbit on the front into the right slot.

RABBIT!

And the blue one, which had a picture of a tank on it, into the left slot.

TANK!

BEST MATCH!

Music from the driver started to play, repeating the tune, until I started twisting the crank, at a slow pace, looking in awe at what I saw. Two transparent tubes came from the driver, making the shape of two pieces of a suit of armour. These became filled with red and blue liquid that gave the suit more detail. In front of me was the front half of the suit, the colour was red. It constructed a left leg with a white spring on the lower area, and a right arm with less armour. Behind me, the other half of the suit was mostly blue and constructing a left arm and right leg. The foot of the leg had a tank tread on it, and the arm being more armoured than the right arm.

ARE YOU READY?!

Striking a pose of crossing my arms in front of my chest and then lowering to my sides, I spoke the magic word.

"HENSHIN!"

Both halves of the armour clamped onto my body with steam hissing from the transformation.

I knew the suit by heart, and every bit of the design. As mentioned, the left leg and right arm are red with half the chest being red diagonally. The right leg and left arm being blue with half the chest being blue diagonally. A black bodysuit was underneath the armour with the helmet finishing the design. The helmet was split diagonally with the bottom half red with a lens that looked like an angry bunny rabbit and the upper diagonal half was blue with the lens looking like a tank with the barrel pointing up.

FULL METAL MOONASSAULT! RABBITTANK! YEEEEEAAAAH!

I lifted my hands to the visor to see them and I was as giddy as a school girl. I raised my right hand and slid it against the tank barrel of my helmet saying the other catchphrase of build.

"The laws of victory are already set in motion"

I ran towards the three Grimm as they rushed to me. As one of them went to slash me, I used the rabbit leg to bounce over the three of them. As I landed, I turned and punched the one who tried to slash me in the face with the rabbit arm… and it hurt me like HELL.

"Ow, ow, ow why did it hurt?"

Then a new voice went off, but different than the last one. This one was more robotic and female. "The rabbit arm is no good for punching but for swinging weapons while the tank arm is better for hand to hand combat." It informed me about the other functions of the RabbitTank form of how it's one of the faster forms of build and how it's used best.

Another beowolf rushed towards me and this time with the voice's help I kicked it in the jaw with the tank foot and sent it flying back. I then ran to the other two and punched one of them with the tank arm while kicking the other.

"Would you like to select a weapon?" the voice asked in a pleasant tone.

"Okay, but who are you?"

"My name is DARCI and I'm your personal AI. I help with combat efficiency and seeing which best match is best for which situation." She replied in a happy tone.

"Cool, what weapons do I have?" I asked, but already knowing what the options were.

Suddenly, more tubes came from the driver and went to my hand to form a type of sword with a drill for a blade, and a black hilt that was styled like a gun handle. It was the drill crusher, like from the show. I gripped the handle with the rabbit hand, gave a chuckle of amusement and ran towards the first beowolf, slashing it across the face and making it stagger. I took the rabbit bottle from the driver and placed it in the slot of the drill crusher

RABBIT! READY? GO!

I pulled the trigger and the blade was covered in red energy.

VOLTECH BREAK!

I slashed the beowolf across the chest killing it, turning it to black dust. I then grab the drill blade and put it in front of the handle turning it into gun mode and fired a few shots at the second Grimm, making grunt in pain. Taking out the rabbit bottle, I placed it in the tank bottle.

TANK! READY? GO!

I pulled the trigger again and a massive blue bullet fired from the barrel of the gun, killing the second Grimm

VOLTECH BREAK!

As the beowolf turned to dust, I heard a growl and looked back to find the other beowolf I had kicked into a rock, running towards me. I re-inserted the tank bottle and started turning the crank on the side of the driver to end this.

READY?! GO!

I ran to the beowolf as blue energy collected around the tank foot, as the tread was spinning and the spring on the rabbit leg allowed me to jump up a few feet and I performed a side kick with the tread still spinning.

VOLTECH FINNISH!

"TANK TREADER KICK!" I yelled as the kick connected to the Grimm and with one last push I went through the Grimm making a hole in its body. As the body disappeared in smoke, I stood there for a minute and thought.

'So, I really am in Remnant. But the question is, which volume am I in?'

"Would you like me to check sir?"

"You can hear my thoughts?" I asked her, a little offended of the lack of privacy.

"Yes we are linked through the Rider system when both in the armour and civilian form".

Now I was interested, as I took the bottles out of the Driver, deactivating the armour. "How so?"

"Through your goggles of course."

I pulled the goggles over my eyes and saw that she was right. On the inside of the lenses was a bunch of stats that showed best matches and analysers.

"Well this is cool. Now which way to Vale? And which volume?" I ask her, as I pick up the case with the rest of the bottles.

"About an hour away and we are in volume 1" she replied happily.

"Then let's go!"

(END SONG)

Later, I'm walking through the streets of Vale and damn, it is a beautiful place. The place looked so real and not like a 3D anime.

"What exactly are we looking for sir?"

I gave it thought. What are we looking for and what are we going to do when we find it. These thoughts clouded my mind so I didn't hear the sound of a motorcycle coming up to me until it was too late.

"Hey watch out!" the bike rider yelled at me as she got closer, and then hit me sending me into a few trashcans.

"Hey you okay?" I heard her ask as I sat up and saw her in full detail.

She had long blonde hair that went really far down her back and bright lilac eyes, she wore a brown jacket over a yellow top that left her stomach exposed, and she had a brown skirt. She also had dark brown combat boots that went to her knees and had a grey scarf around her left knee. Finally, she had black fingerless gloves and yellow bracelets, which I knew were actually shot gun gauntlets, and an orange bandana around her neck.

'Oh god' I thought to myself.

'What? Do you know her sir?' DARCI asked me.

'It's one of the main four characters from RWBY. Yang Xiao Long.

A/N: Okay that's the first chapter of my fic. Please review and help in any way you can, flaming won't be appreciated. All in all tell me what you think.

BYE, BYE.