Pokémon Kyanite and Copper (Revised Version)

Third person POV

 Marshall's Luxio then charged at Riolu and used Bite, biting Riolu with viciously sharp fangs. "Dodge that and use Karate Chop!" Rico immediately and seriously commanded Riolu. Riolu did so and used Karate Chop, attacking Luxio with a sharp chop. Luxio got struck by it.

 "Luxio!" Marshall responded to this.

As Luxio tried to snap out of pain, Rico said to Riolu, "Wow, good job, Riolu!"

Riolu then responded with serious toughness.

Luxio managed to snap out of being in pain, and Marshall responded to this, "Well, nice Karate chop your Riolu have, but can you handle this?"

Then to Luxio. "Use Quick Attack!"

Luxio then used Quick Attack, charging at Riolu at a fast pace.

 "Be on guard, Riolu," Rico said to Riolu.

Riolu nodded with alertness.

But then, Marshall commanded Luxio, "Then use Bite, now!"

Luxio did so, and Riolu was caught off guard, getting struck by Luxio's Bite attack.

 "Oh, no, Riolu!" Rico responded to this while being surprised with stunning.

Jonathan and the others were surprised to see that.

 "Woah, Luxio switched moves to outsmart Riolu!" Jonathan commented.

Litleo and Jonathan's Boldore then responded with stunning.

Riolu was in pain but managed to hold on.

 "Quickly, Riolu," Rico said to it in commanding, "use Karate Chop!"

Before Riolu would use that, Marshall immediately commanded Luxio, "Use Discharge, Luxio!"

Luxio did so, striking Riolu with a discharge of electricity.

This time, Riolu was defeated by it, and Rico was mildly shocked by it.

 Jonathan then acted as the battle's referee and announced, "Riolu was unable to battle. Luxio wins." Marshall and his Luxio were happy with victory. Rico, luckily, accepted his defeat and held Riolu's Poké Ball, calling Riolu back. "Okay, Riolu, you did a good job. Get some rest."

After that, the young Kawayan boy put the Poké Ball back into his Pokébelt and looked at Marshall positively. "You were strong actually. I had done my best. That was a good battle we had."

Marshall was amazed and stunned. "Wow, thanks, Rico. Someday, you will win against me."

Rico and the others were happy to hear that, and Rico was more determined to train harder.

 Later, all of them were returning to the communal home of Marc and Marshall's relatives on foot when Marshall asked Rico and Jonathan, "Hey, Rico, Jonathan-san, can I be your travel companion when you guys travel this region after this?"

Rico, Jonathan, and their Pokémon teams looked at him with surprised looks on their faces. 

"What?"

 "You want to come with us?"

Marshall then nodded. "Yes, I'll be of good use to you guys, and I even have some practical and good technology from my old days that would make our journey slightly easier."

Rico and Jonathan eventually accepted his request.

 "Sure."

 "It'll be more fun when more people come with us in our journey."

Their Pokémon then agreed with their Trainers' decision.