Long ago in the Kalos Region, when the land was mostly forest, there lived a young man. More precisely, he was the heir to the throne of the Kalos region, and because of this he lived in a large castle at the top of a mountain overlooking the entire region. The mountain was home to many pokémon, and the people of the castle created wonderful gardens that cascaded down the mountain's sides. The young man loved to play in the gardens because he loved pokémon and always liked to see how many different kinds he could find. One day, while he was running down the mountain path, he saw something sitting at the edge of a steep cliff. Unable to overcome his curiosity, he walked over and saw several liepard crouching at the cliff's edge and staring downwards. He could hear them growling and hissing, and tried to stay a little ways away to avoid being attacked. From his hiding spot behind a tree, the young man got a glimpse of what the liepard were looking at. On a smaller ledge five feet or so down the cliff a deerling was frightfully clinging to the slumped shape of a sawsbuck. Judging by how much dust covered the deerling's pink spring form coat, it looked as though it and the sawsbuck had fallen. The young man couldn't help but do something; he couldn't stand to see a helpless pokémon be devoured by the liepard. He grabbed a small rock that lay at his feet and held it in the palm of his hand as he waited for the right time to throw it.

"Aleron, I can't reach them!" a female liepard yelled as she failed at another attempt to hook the deerling with her claws.

"Well, keep trying, Nadine! We don't have all day!"

Nadine reached down with her paw as far as she could, her claws missing the deerling's nose by a few inches. "I still can't!"

Aleron rolled his eyes. "You're so lazy. Just reach a little farther. And do it quick, I can feel my stomach eating itself!"

"If you think it's so easy, then you do it, pea-brain!" Nadine screeched, her whiskers and tail twitching in anger.

"Oh, you want me to now? You said you could do it yourself!" Aleron yelled back, his green eyes seething with rage.

"When did I say that?" Nadine hissed back.

The little deerling stopped watching the two liepards as they started to argue and forget she was even there. She looked back toward her mother, the sawsbuck, and pressed her face against her side. She could feel a slight movement from breathing, but nothing as strong as she had remembered. She suddenly looked up as she heard a noise. The liepards had been startled by something and were running away, abandoning their potential meal. The face of a human appeared at the top of the cliff, and the deerling watched as the human carefully slid onto the little outcrop she was on.

"It's okay, I'll help you," the human said to her cautiously.

The deerling shook her head and slunk back towards her mother. The fur was even colder than before and the movement had stopped.

"You can't go back with her," the human added, analyzing the sawsbuck carefully. "she's not…alive anymore."

The deerling flinched as she heard those words, knowing their meaning. She peeked up at the young man, wondering if it was best to live in the wild by herself or go with him to wherever he would take her. Either way it was risky; she hadn't even been with her mother long enough to remember her own name. Her mother hadn't had time to teach her many survival skills either. The deerling slowly made up her mind, took her head out of her mother's cold fur, and stepped towards the young man. He grabbed her and carefully made his way up the cliff side until he was back on the grass. The deerling could barely stand up for being so weak from the fall, so he carried her all the way back to the castle at the top of the mountain.

They eventually made their way into the castle past the royal Aegislash guards. The young man ran frantically through the castle's many halls and corridors as the banded highlights and shadows of the windows rushed by, and didn't give a second thought to anything around him. He only stopped when he came to a large musty room that smelled of herbs. A scrawny old woman dressed in rags was chopping up leaves near the back wall, zoned out from the world around her.

"Hilda," the young man called over to her. "I have something here that you need to see."

Hilda, not the least bit startled at the young man's frantic call, put down her knife and turned around. "What is it Aldrich…oh my!" She quickly ran over and looked upon the injured deerling with a wise and experienced eye. "I will get you back to good health." she said, knowing the problem before Aldrich could explain. She quickly gathered up some herbs and started to mash them in a bowl with water. Aldrich just watched her, wondering how she could figure out things when he hadn't even explained anything yet. She had always been an interesting and mysterious woman, and there were rumors in the castle that she had magical powers. Aldrich's father had once told him that when he himself was a little boy Hilda had showed up at the castle insisting that she get a job there to help guide Kalos's future. This made absolutely no sense to everyone that saw her at the time, but she was a nice and caring lady that could heal many ailments, and Aldrich's grandfather accepted her as part of the royal staff. Despite her seemingly very old age, her habit of always wearing rags, and her bony appearance, she was as young and sprightly as ever, and Aldrich was happy to call her his friend.

The deerling was also mesmerized by how the strange, hunched woman effortlessly blended the herbs into a life-saving formula, but her fatigue was so great and her eyelids so heavy that she couldn't help but slip into darkness. As her consciousness ebbed away she thought she heard Hilda whisper in her ear.

"I have been waiting for you for a very long time, young one. Whatever happens, I will be there to guide the future of Kalos."

The deerling awoke on a cushioned pokémon bed, remembering all at once what had happened recently. She looked around at the room she was in and noticed a large, ornate human bed against the far wall. This must be Aldrich's room, she thought to herself. She was jolted out of her thoughts when she heard a muffled sound coming from the opposite end of the room. She slowly crept out of her bed, making sure to place her hooves on the wooden floor lightly so they wouldn't clop. She crept up to the bed and saw that Aldrich was sleeping soundly in it. He suddenly awoke as he sensed her presence and looked at her fondly. "So, you're awake now," he said happily as he got up and placed his feet on the floor. "I was talking to my parents during the few days you were asleep and they agreed that it would be best if you stay here."\

The deerling cocked her head to one side and uttered a questioning mew.

"What I mean is," Aldrich continued, "would you like to be my pokémon from now on? You don't have to if you don't want to."

The deerling thought about this. She had nowhere else to go anyway; her mother was dead and hadn't had enough time to pass on her survival skills.

Finally making up her mind, the deerling nodded yes.

"Wonderful!" Aldrich replied. "But you need a name now. Let's see, what should it be?" he furrowed his brow in thought. "Oh, I know! Your name shall be Xerneas, after the goddess of beauty that my ancestors used to worship. I think it fits you perfectly!"

Xerneas… she ran the name through her head, liking the ominous ring it had, and jumped into her new trainer's arms happily.