Name: Jack
Age: 2
Weight: not much
Height: not much either
Powers: Unlimited need to do violence
Jack was a white lab rat used in a university study to try out a new medication that would make people less violent. In order to properly test the drug they first needed a violent test subject, so Jack was chosen to be turned into a psychopathic rat.
A machine was constructed that would fill Jack's mind with murderous thoughts. Jack was placed inside and the machine was powered up. Almost immediately the indicators on the machine showed Jack's mind absorbing the input and becoming more and more warped. Then the doctor performing the experiment got a phone call in his office. He instructed his assistant to watch the progress and as soon as Jack's mind was full, to turn the machine off.
The phone call lasted longer than he'd expected, and a full half hour had passed before the doctor returned. He was amazed to see the machine still on. The assistane explained that somehow the rat's brain had been altering itself to better be able to soak up the thoughts the machine had been placing into his brain.
Terrified at the implications, the doctor ordered that the machine be immediately shut down. As the machine turned off, the doctor looked inside and found what appeared to be an ordinary rat looking up at him, twitching its whiskers innocently. When he tried to touch it, it darted out of the way and jumped out of the machine landing on the table. It scurried off among the many scientific implements lining the table.
The scientist and his assistant started to search through the maze of things, looking for the rat that they thought must have been terrified. As the doctor examined a dissecting tray, Jack jumped out from behind some beakers and landed on his chest, clutching something shiny in its paws. The doctor batted at it, screaming, but the rat scampered up his chest and sliced his throat open with the bright scalpel it was holding.
As the doctor collapsed, the lab assistant watched, transfixed with fear, as the white rat, its fur sodden with red gore, clutched its scalpel lovingly and whispered "Pretty, pretty, pretty..."