I don't own anything related to pokemon save several of their games, including but not limited to a Ruby and Omega Ruby.
Each of your pokemon has a summary that lists it's type, nature, original trainer, and various other things. One of these things is how you met. I had recently transferred my Swampert that I had used in my original Ruby game to Omega Ruby and was comparing it to my current Swampert, despite my new one being at least 20 levels lower, when I noticed the description of how the original Swampert was met.
"Seems to have travelled across both space and time to reach you from the Hoenn Region."
I had a fangasm. Until I realized that that description wasn't limited to the original Hoenn game pokemon. But my mind asked this question:
"Why would a pokemon travel through time and space to reach a you?"
The next thing I know I had wrote this.
PS: The chorus of I'm Coming Home by Diddy-Dirty Money and Skylar Grey played through my mind as I wrote this. It seemed appropriate.
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Tide watched the box that held the body of his trainer being lowered into the ground.
Why?
Surrounding him were the other pokemon his trainer had caught, and on the other side stood the parents of his trainer and all the friends he had made.
Why did this have to happen?
As the priest continued with his speech, the Swampert's mind once again plagued him with memories of his trainer's last moments.
I'm Coming Home, I'm Coming Home
"Tide! Dodge and then hit him with another Hydro Pump!"
The Swampert quickly jumped out of the way of a Fire Blast and fired the Hydro Pump at the massive form of Primal Groudon.
The battle had been raging for several hours. His trainer had sent out his whole team from the beginning in their attempt to stop Groudon. And while the Legend was tired and weakened, it was still powerful, and all of Tide was alone and tired, his teammates having fallen unconscious or been badly injured and their trainer's supplies were spent.
Groudon roared in pain as it was hit by the powerful blast of water before shrugging it off and stomping it's foot, initiating an Earthquake.
Tide fell to his knees as he lost his footing, before a Hammer Arm sent him tumbling across the ground. Gritting his teeth from the pain, he shakily rose to his feet.
"TIDE! LOOK OUT!"
Tide looked up at his trainers yell, only to see Groudon aiming a Solarbeam at him. He moved to dodge, only for his left leg collapsed, and his eyes widened as the Groudon's attack was fired at his helpless form. He closed his eyes and braced for the impact, only form something to knock him to the side. His eyes snapped open just in time to see the Solarbeam blast his trainer into the wall.
NO! NONONONONO!
Tide dashed to his trainer's side, his horrified eyes taking in the mangled arm that had taken the brunt of the impact with the wall, the large burns from the attack, but most of all the blood pooling from the back of his trainer's head. His trainer opened his eyes and looked up at him as the last words were spoken , "Tide…Please…Survive."
Despair filled Tide's body, but was quickly replaced by pure rage. He gently set the body down before turning and charging at his foe.
Tell the World I'm Coming Home
Everything from that point was a blur, but Tide vaguely remembered limping away from the fallen Legend, picking up his trainer, and carrying him out of the cave.
He shut his eyes and he clenched his fist, his anger spiking at how he was powerless to save his trainer; the one who had chosen him, a young shy Mudkip, over the rowdy and friendly Torchic or the calm and prideful Treeko. The one who he had fought for through countless trainers, from Youngsters who were just starting their journeys to veteran Gym Leaders. He would do anything to change the past-
An idea stuck him, a plan that was so unlikely to succeed, but one the the Swampert seized. Tide's eyes snapped open, his tears dried and his eyes now filled with sheer determination, as he turned and ran.
Let the Rain Wash Away, All the Pain of Yesterday
It took three years to finally find her.
And now Tide stood before the Legendary Celebi, having pleaded with her to allow him to go back and save his trainer.
"I'm truly sorry," Celebi told him, "but I can't truly change the past. The only reason I take people or pokemon back is because they had come back."
Tide's fists clenched as he lowered his head. He had travelled so far, and been through so much, only for his only hope to fail him.
"But-" Tide's head snapped up, as hope once more filled his heart. "There is a way. I normally wouldn't mention it, but you and your trainer was responsible for stopping Groudon. If you can somehow convince them, Dialga and Palkia are capable of what you seek."
He thanked the Forest Guardian before once more setting out on his quest.
I know my Kingdom Awaits, and They've Forgiven My Mistakes
When Tide had tracked down the Legends of Time and Space six years ago after two years of searching, he had once more pleaded his case, only for them to refuse. Angered and desperate, he challenged them and their decision. The ensuing battle was a complete loss, despite the training and experience he had gained during his searching. Thankfully the Legends had given him one more chance. He was allowed to train for five years, and then try again, but if he failed that time he would receive no more chances.
And know Tide panted as he stood across from his opponents, staring at them with raw determination, even though he was so tired he could barely stand. Dialga and Palkia, both pushed farther than they ever had by a "common" pokemon (Especially with them working together!) shared a look as the Swampert attempted to walk towards them and continue the fight. They nodded at each other before Palkia surged forward and caught their opponent as he began to collapse from exhaustion. "Sleep." He told the Swampert, "You have truly impressed us, and we shall grant your wish."
I'm Coming Home, I'm Coming Home
The first thing he noticed as he began to wake was that it was extremely hot.
The next was the sound of a fierce battle being waged.
The third, however, was what truly woke him was a voice a voice he hadn't heard in ten long years. He shot to his feet, only to nearly collapse in joy at the sight of his trainer, leading his team against their opponent. But then his eyes narrowed as he turned to look at the pokemon he hated above all others.
This time he would not fail.
Tell the World I'm Coming Home
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
…THE FEELS! (Starts crying uncontrollably.)