The next day at the Pokemon school Ash came with a Rotomdex a Pokedex with Rotom in it. 

Everyone was amazed by it as they never seeing something like this before.

Later that day everyone went out to help Ash and Y/n find and catch some Pokemon. As they were looking Rotom found out about Y/n's team of legendary Pokemon and was begging him to let them out for pictures.

As they searched they found a Pokemon that looks a lot like a Pikachu. 

"Mimikyu the Disguise Pokemon a ghost and fairy type. It wears a ragged head cover to look like a Pikachu, but little is known about this Pokemon. It's said that a scholar who one tried to look inside met his end". Rotom informed after he took a picture.

" Awesome let's catch it Pikachu". Ash said wanting to catch it. "Pika" ! Pikachu yelled as he got ready. 

When Pikachu faced it, the Mimikyu seemed to let out a dark aura that Y/n sensed. Mimikyu attacked Pikachu aggressively with play rough. At that moment Y/n noticed Mimikyu's aura is filled with rage and anger for Pikachu.

From the bushes came the infamous and annoying trio that Ash know's all to well.

Cue their motto here I'm just lazy and thinking about what team idiots do or say will give me a headache.

 "Team rocket!" Ash growled. Pika.... Pikachu growled like his trainer.

"You know these idiots Ash?" Y/n asked as he reached for his Pokeballs. Already having a feeling they'll be a massive pain in the neck in the future.

"Yeah they're team rocket, they always try to steal Pokemon from others" Ash explained.

This caused Y/n to get angry, he hated anyone who'll steal from others.

"Not if i can help it " . Y/n said. 

Y/n threw his three heavy balls, calling out his three golems.

Team rocket was shocked and scared of the sight of the three legendary golems , never once thought they would face them here in alola .

While Y/n's friends saw them before, they can't help be in awe of the three legendaries infront of them. Rotom however was the most excited as he took pictures of them while scanning them.

"Regirock the Rock peak Pokemon a rock type. Regirock's body is made if rock, and if something chips off in battle, it attaches rocks to repair itself."Rotom said as he took a picture.

"Regice  the iceberg Pokemon a ice type. Formed in the ice age, its body stays at a temperature of - 328 degrees and cannot be melted, even by magma." Rotom said as the snapped a few photos. 

Registeel the iron Pokemon a steel type. Registeel has a body that is harder that any kind of metal. Its body is apparently hollow. No one has any idea what this Pokemon eats. Rotom said as he took a few pictures. 

I wonder if its body is really hollow. Rotom wondered as he tapped Registeels body a few times, annoyed by the taping Registeel knocked Rotom away.

Rotom hits regice's body freezing him in seconds, Regice broke Rotom out, leaving the living Pokedex shivering from the cold.

The regis looked at the trio infront of them, they could tell they are they are ones that angered their trainer, and are now ready to blast them to a new age at Y/n's command.

" Alright you three use hyper beam." Y/n called out his command.

The regis "eyes" flashed and beeped, each charging a orange ball of light ready to fire.

Team rocket were hugging each other shivering from fright, until a pink and black Pokemon came and picked them up and took them somewhere, team rocket was just as confused as they said " we're off with a new blast?" 

"Huh? Who's that Pokemon?" Ash asked?

Bewear the strong arm Pokemon. A normal and fighting type. Bewear has extremely powerful arms, and it's very dangerous. It waves its arms in a friendly fashion, but this is a means of warning. Approach with caution. Rotom informed.

"Noted" Ash said remembering his last encounter with the strong arm Pokemon.

"It's to bad that Mimikyu got away". Mallow said.

At that moment Y/n felt an strong aura coming their way.

"Guys heads up, something coming". Y/n warned the others of the aura he sensed.

From the shadows came a Pokemon that looks like a small human. 

"Huh who's that Pokemon?" Y/n asked with the others wondering the same thing.

Rotom was shocked at the sight of the new Pokemon.

No way!!! That's marshadow A legendary Pokemon. Rotom said still in shock at the sight before shaking it of and scanning it.

"Marshadow the gloomdweller Pokemon a fighting and ghost type. It sinks into the shadows of people and Pokemon, where it an understand their feelings and copy their capabilities.

"I heard of it before". Lilie said. "It said to hide in the shadows of people and Pokemon like Rotom said, but it rarely show itself to humans to the point that not many are sure that it exist."

"If what you're saying is true, why did it show itself to us"?  Y/n asked.

Marshadow looked at Y/n and let out a battle cry as he attacked him.

"Woah" Y/n yelled as he ducked out of the way.

Y/n's Pokemon reacted and used zap cannon but marshadow dodged them all before jumping a few feet infront of Y/n.

Marshadow called out a challenge to Y/n. Understanding that Marshadow want's a one on one battle, Y/n called out Diancie.

"Diamond storm"! Y/n called out.

Obeying , Diancie fired pink diamonds at Marshadow, only for it to dodge with shadow sneak and hit Diancie with ice punch. DIA!!! Diancie cried out in pain. Y/n called out a moon blast which was countered with shadow ball.

Diancie jumped back to Y/n as the two got ready. Y/n held his keystone as he began to chant.

You who has the strength to evolve even further, Y/n began. If you lend me your heart and trust, I shall lend you my strength and will. The mega stone on diancie and Y/n's keystone let out four streams of light that started to connect together as Diancie's body glowed and began to change. Transcend through the boundaries that keep you true strength hidden away! Beyond evolution, Mega evolve!! As Y/n finished his chant, Diancie has finished changing , her new form shined as the mega evolution symbol appeared for a second before fading away to reveal her mega form.

"Wow amazing"! Lilie said. "Incredible"! Mallow said . " So awesome" Lana said with stars in her eyes.

The boy's were speechless, unable to say anything from awe. Rotom was taking pictures like no tomorrow, and started to scan Diancie.

Diancie the diamond Pokemon a rock and fairy type. A sudden transformation of carbink, its pink, glimmering body is said to be the loveliest sight in the whole world.  

"Now Diancie moon blast "! Y/n called out. Diancie fired another moon blast, but it's larger the last one. Marshadow tried to counter with shadow ball, but the moon blast broke though and hit marshadow hard and knocking it back hard.

Marshadow tried to get up but was to weak. Marshadow smirked as it found a trainer worthy of catching it.

Y/n understood the silent massage and threw a dusk ball at it. 

The dusk ball shook once, twice, thrice and ding. And with that Marshadow is caught.

"Alright!" Y/n cheered.

The others came and gave their congratulations as Diancie turned back.

"Thanks you guys" Y/n said before looking at Diancie and thank you to Diancie i couldn't have done without you have a good rest.

Diancie let one more happy cry before Y/n returned her. Y/n also returned the regis after thanking them.

 " That was awesome Y/n, i'm going to catch a Pokemon for sure". Ash said more pumped up than ever.

After that they all continued there search for another Pokemon, one that Ash can catch. What kind? read to find out.

 Man that was tough, this was not easy write. My brain is smoking from how much i'm pushing it. So Marshadow has been caught, Marshadow wanted to grow stronger but the trainers he met in his past were to weak for it, when it sensed Y/n's aura he knew Y/n is strong but he wanted to test him.  So next time Ash and Y/n will meet a Rowlet in a group of pikipek?