Disclaimer: I don't own anything. Neither RWBY nor Kamen Rider

Journey Through Remnant

Chapter 2: The Breach

Tsukasa normally doesn't give it his all when fighting, be it against monsters or other Riders. Seeing as whatever these black animals were part of the former category, he still held back.

The monsters themselves tend to fall from a few shots and slices from his RideBooker, so it wasn't a problem for him. The problem was that the courtyard had a good number of civilians who weren't able to get out in time. That and the fact that many are continuing to come out of the opened ground, including some sort of black and white snake with heads on both ends. Until that gets sealed up, more monsters will keep coming.

Already knowing how to solve the first problem, Tsukasa tried to figure a solution to the other. 'Wizard? Maybe.', He thought as he cut down two more of the black monsters. Hearing a loud crash nearby, Tsukasa turned to his side and saw a car had been thrown at a group of monsters.

'Right, them,' The people that had been thrown off the train from earlier had woken up. A group of 4 teenage girls was normal to Tsukasa; carrying weapons and fighting the monsters wasn't. It wasn't the weirdest thing he has seen; a time-traveling train will continue to be number one. They were doing a pretty good job in Tsukasa's eyes. However, like him, they are only dealing with the symptoms and not the cause. Said cause being the large hole in the ground.

'That form should be able to deal with it,' Tsukasa decided. Before he could start with his plan, Tsukasa heard a loud gunshot from the sky. Looking up, he saw someone in pink shooting through the sky, balancing on a large hammer and striking one of the heads of the large snake. 'Emu would love to hear about this.' Tsukasa should visit the Doctor/Gamer more often.

The new arrival landed nearby, and three others joined her, wielding their own weapons. One of them, a red-headed teenage girl with an armor set like a Spartan from ancient history equipped with a shield and a shortsword, ordered the others to move out. 'This world has a lot of teenage warriors.' Decade thought before focusing on the waves of enemies before him.

Not even twenty seconds later, a giant bear version of the monster appeared and approached one of the teenagers that had just arrived, a blonde-haired boy that wore a simple hoodie and jeans with very little armor and had a sword and shield. However, the boy managed to gather enough confidence and wildly slashed at the giant bear, killing it.

From on top of some of the courtyard stairs, Tsukasa saw a couple of faces he didn't think he'd see again so soon. Sun and Neptune had arrived, the former announcing while the two showed off their badges, "Nobody move! Junior Detectives!".

"We have badges, so you know it's official." Neptune continued full of confidence.

The two fist-bumped, but before they could join the battle, the sky rumbled. 'What now?!' Tsukasa once again looked up. A large airship with a fleet of other much smaller airships was not something one would normally see every day, so for the first time since waking up in this new world, he was genuinely surprised, though it still paled in comparison to that one airship Dai-Shocker had.

'Whatever, I have to deal with the citizens.' With that note, Tsukasa opened the RideBooker and took out another Rider Card. The Rider depicted in the Card was red with a Kabutomushi motif. The symbol on the back of the card was of a Kabutomushi with the word ZECT going through the center. Starting the first step in his plan, he inserted the card into the Neo DecaDriver.

KAMEN RIDE: KABUTO

Tsukasa's suit got covered in hexagonal pieces before a new armor was formed. His new form was mostly black, the sides of his legs and arms having some silver pieces of armor. His shoulder pads were much smaller and were silver and red, much like the new chestpiece. Finally, his helmet was smaller, with large blue visors and a large red singular horn splitting it. This new form belonged to the man who walked the path of heaven, ruling over all. Kamen Rider Kabuto.

His new transformation had caught the attention of all the fighters in the area, but Tsukasa paid them no mind. Without any hesitation, he got a new card out, this one depicting Kabuto moving with some afterimages before him, and inserted it in his Driver.

ATTACK RIDE: CLOCK UP

Within seconds, all of the civilians who couldn't get away in time found themselves on the other side of the courtyard, far away from the animalistic monsters. To everyone else, Tsukasa had become a blur and moved the civilians away, but to him, time itself had slowed down immensely. He ran through the horde of monsters, slashing at them and rescuing the civilians.

Coming out of Clock Up, Tsukasa was about to continue to step two of his plan when soldiers came dropping in from the airships. Said airships were also were giving covering fire with the guns that were attached to it.

More reinforcement had arrived in a short amount of time, including another team of 4 teenagers, one of whom was equipped with a minigun of all things. The horde of monsters was starting to thin out by a lot, but more were still coming out of the hole. Speaking of it, a man and a small dog had come out of it, helping kill the monsters. Fighting alongside a dog was new to Tsukasa. Although he had once fought alongside a Space God, the dog was still bizarre.

Still, the hole needs to be sealed up. Tsukasa took out another Rider Card, depicting a Rider with a helmet with a hawk motif. Inserting the new card into the Neo DecaDriver, he transformed again.

KAMEN RIDE: OOO

Taka! Tora! Batta! TaToBa! TaToBa TaToBa!

In front of Tsukasa, three large spectral medals manifested, the top being red and had a hawk engraved on it, the middle was yellow and had a tiger, the bottom being green and had a grasshopper on it. The three medals fused and formed OOO's symbol before sticking to Kabuto's chest. A new suit formed, the undersuit being black. The helmet was the same as depicted on the card with bright green visors, the arms having gauntlets that were yellow with some claws folded in, and legs that were a simple green with minimal design. Finally, the chestpiece had the symbol of OOO on it.

This new form was that of Kamen Rider OOO and belonged to a man that had no desire. Tsukasa, however, wasn't going to use this form for long. Taking out another card, he quickly inserted it into his Driver and closed it.

FORM RIDE OOO: SAGOHZO

Sai! Gorilla! Zoh! SaGohZo... SaGohZo!

Three new medals manifested, all being a shade of silver and had a rhino, gorilla, and elephant engraved on them. The medals fused and stuck to his chest, changing Tsukasa's form once again. His new form kept the undersuit. However, the helmet has changed into the single-horned silver rhino with red visors, the gauntlets and shoulder pads were much larger and silver in color, and the legs were a pitch-black color. This was OOO SaGohZo.

Tsukasa didn't have much experience with this form, but he had seen Eiji Hino, the true Kamen Rider OOO, use this form several times, so he was aware of what it was capable of. Only one of which its abilities were of use to him right now, gravity manipulation. Without thinking, Tsukasa started to bang his fists against the chestpiece of the suit.

The effects were near-instantaneous. Some of the monsters who were smaller than their peers were starting to float along with some debris. This was Tsukasa's goal. Using SaGohZo's powers, he forced all the debris that had gathered from the battle into the Breach and sealed it up, preventing more of the monsters from coming.

Now that that was taken care of, Tsukasa reverted into his Decade form to deal with the last of the horde.

From afar, a certain duo was watching the Rider. One was a fair-skinned silver-haired boy, and the other was a darker-toned green-haired girl. The two were evaluating him, trying to figure him out. One said to the other, "We have to tell Cinder."

Tsukasa watched as two people escorted a red-headed man in a nice hat and suit into an airship, now out of his Rider form. Normally, by now, the Rider would have left to go to God-knows-where, but 17 people were blocking his exit. He could just open a Dimensional Wall, but this world was starting to interest him.

Of the 17 people preventing him from, 3 of them were adults, one of which was rambling very quickly. All Tsukasa knew was that he was asking about his abilities. Granted, it wasn't only the man asking him; most of the teens, including Sun and Neptune, also questioned him.

One of the adults, a blonde woman, cleared her throat to get everyone's attention. "First things first, what is your name?" The woman asked Tsukasa. Before he could answer her, Neptune did the talking for him. "His name's Tsukasa Kadoya. Sun and I bumped into him earlier." Neptune said with a smile upon his face.

"Alright then, what were you doing here, Mr. Kadoya?" She continued interrogating him. Without missing a beat, Tsukasa answered, "Relaxing."

She thought about his answer for a moment, trying to figure out if he's lying or not. Regardless of whether she concluded to, the woman continues to ask him questions, "Where did you get your powers?"

"Secret." Tsukasa wasn't going to tell anyone the origins of the Neo DecaDriver anytime soon.

The woman grimaced for a moment before continuing, this time with an order, "I must ask that you come along with us to meet Headmaster Ozpin."

Whoever this Ozpin was didn't matter to Tsukasa. Right now, he was trying to figure out his role in this world, if he even has one. Maybe this Headmaster might help him with his goal, "Okay."

The woman visibly didn't think he'd accept so quickly, as her face showed her surprise at his answer. She collected herself quickly, nodded, and gestured to one of the airships, "If you would follow me." She said as she walked towards it with the others.

As he followed them, Tsukasa went back to thinking. As the airship took off, he thought more of his situation. For some reason, he's been getting a sinking feeling on his stomach. Whatever is going to happen now will be very important to the future of this world.

Destroy Everything!

Connect Everything!

A/N: I have insomnia, so this chapter came up in less than 12 hours. To me, Tsukasa is one of my favorite Riders, so I may accidentally make him too OP. Regardless of which, please review.