As a Kamen Rider standing before him, Y/N assess the situation he is in. He had never seen the man in front of him ever in his life. He pondered for the moment, having thoughts of running away from the fight just to help his friends, or stand his ground and fight.

Y/N: I don't even know who you are!

???: I am Nightrouge! I was sent here to retrieve the power that you have by the Dark Knight.

Y/N: Dark Knight? Look buddy, I don't even know who or what does he want from me. All I know is that this power is mine alone!

He yelled as Nightrouge scoffed as he aim his transteam gun at Y/N as he started to open fire at the H/C haired man. Without any hesitation he started to dodge all of the shots, taking cover as he regroup.

Nightrouge: You won't be able to hide forever. It's fight or flight from here on out!

He yelled as he opens fire once again, as he saw a small glimpse of Y/N's figure as he went to hide on another area, trying to find a way to fight him.

Y/N gritted his teeth as he decided to use his Chemokinesis as he took a big breath, blowing it out as smoke started to fill the area having to use this as his advantage as he looks at Nightrouge.

Nightrogue: This fog won't stop me!

He yelled as Y/N made a move, running towards another hiding spot, as soon as Nightrogue saw his shadow, he started to open fire. As he pulled the trigger, sparks started to happen as it ignited an explosion on his side, sending him back a couple of meters away as he groaned in pain.

Y/N: Hurts doesn't it?

Nightrouge: What did you do!

Y/N: That smoke is made out of methane. I am well aware that you are familiar with it?

He asked as the smoke starts to clear up, revealing Y/N standing across Nightrouge wearing a driver on his waist.

Nightrouge: So, you're going to use your borrowed power after all.

Y/N: My power is mine and mine alone, and if you think you can take it away from me, then I would like to see you try!

He said as he holds two bottles on his hand as he starts to shake them.

Mathematical equations started to float in the air as he stopped twisting both of the caps as he places them on their respective slots.

Build Driver: Rabbit! Tank! Best Match!

He cracked a small grin as he started to turn the lever on the side of the driver for a couple of times as he stops, once the armor is at full picture.

Build Driver: Are you ready?

Y/N: Henshin.

The red and blue armor started to close in on him, releasing some steam once they are in a perfect fit as he does some small gestures.

Build Driver: (Techno rock music) Hagane no Moonsault! RabbitTank! Yeahhh!

Nightrouge: So, you went with Build. This is going to be easy.

He said as he started firing, closing in on Build as he fires. Build took a deep breath as he started to run over to Nightrouge, showing his Drill Crusher in sword mode as he blocks them away.

Once he was close, he started to swing his sword, fending off Nightrouge as he blocks them with his gun. Back and forth they go as neither of them are making a hit on their opponents.

They broke away from their fight as they gain some distance as they look at themselves for a moment.

Nightrouge: I never would of thought that someone would be using this power for worthless things.

Build: Say what you want. All I know is, I use this power for the greater good!

Nightrouge: Then I'll take that power off of your corpse!

He yelled as Y/N throws some sphere towards Nightrouge as he started to change the form of his Drill Crusher in gun mode as he started to shoot the sphere.

The shot made contact as the sphere exploded, having Nightrogue sent flying a couple of meters more from the explosion.

Build: I didn't join the Fire Force Company if I didn't even use my gifts right.

He said as he throws another set of spheres towards Nightrouge, being perceptive as he is, he didn't shoot at it as the sphere lands near him, releases a clear colored gas.

Nightrogue: What is...this...

He said as he slowly started to take a small whiff of it, making his body calm as he sways a little bit.

Build: That gas is used for subduing people, to make them calm when an infernal appears. Making them calm and collected during evacuation measures.

He explained as Nightrogue was having a hard time looking at Build, his visions started to get foggy as he looks at him. Build turned the drill into its sword mode once again, pulling the rabbit fullbottle out of its slot as he places it on the drill's slot.

Drill Crusher: Ready, Go!

Build: Return to the great flames!

He said as his drill started to rotate on a high speed, charging towards Nightrogue as he swings down the drill towards him, making a direct hit.

Drill Crusher: Vortex Break!

As the final attack was delivered Nightrouge fall down on his knees as he looked at Build one last time.

Nightrouge: You think that this is over? When one falls, another one rises. I'll see to it that borrowed power will no longer be yours.

He said as he slowly falls down, his body started to break away as Build de-henshined turning back to normal.

Y/N: Then I'll make sure that I will protect this no matter the cost.

He said softly as he started to run back to his team, wanting to know if they were okay despite an explosion happened moments earlier.

To be continued...