Sparky the Chu
Sparky was one of three Pikachu born in the woods to two loving parents, who were the strongest of their kind in the forest. His brother was large, and had powers of electricity that were as strong as his father's. His sister had the beauty and control of her mother, and even if she lacked the sheer muscle of her brother, she could beat him as often as he beat her by using her electric attacks in ways no one else had ever seen before.
Sparky was not so big, and not so strong. Nor did he have control as his sister did, for his power would come in hiccoughs, there and gone again as fast as the blink of an eye.
One night, Team Gamma, a group Pokémon hunters, entered the forest. Grabbing random Pokémon, they selected the best and the brightest. In Sparky's case, they found that his siblings were the best, and chose to take him instead, feeling that if they could discover why he had not turned out that great, they would be able to unlock the potential of all the others they had captured.
So it was that Sparky awoke to find himself locked in a cage, in the hands of the Team Gamma scientists. Sparky would, for a time, submit to their testing and experiments, gaining many new powers. One day, one of the scientists, seemingly without meaning to, left the keys to the cage laying nearby. Sparky used a small amount of electricity to turn the bars of his cage into magnets, attracting the keys so he could escape.
Sparky got out of the Team Gamma base by hiding in someone's shoe, and emerged in a restaurant. Hungry, Sparky snuck into the kitchen, and hid himself in a small hole he ate into the side of a steak. When the steak was served to a young boy, Sparky was swallowed whole, but, to his surprise, reformed afterwards and fled.
Sparky is a wanderer now, without a home or the family of his youth. He makes his way through life, always trying to have fun and give the same fun to others.