Billy Cord was the local sneak thief at the Martin Sammish High School in Sacramento, CA. He had a thing about ninjas, and didn't have the common sense to not broadcast it.
On March 7, 2007, Billy and eleven other students were removed from school under false pretenses and subjected to an experiment intended to create Dynamorphs—in the process turning the kids into Dyna-Hosts and changing the genders of a few of them. Before there was a chance to extract the dynamorphs from the test subjects, however, they managed to escape.
Billy is able to manifest four tentacles from the sides of his body. These tentacles can be long enough, and strong enough, to pull a person from a room. They also allow him to climb walls.
With the help of a dynamorph-housing crystal the group recovered from their opponents, Billy has the ability of appearing like a sort of "blot of darkness", becoming invisible in shadows.
Mentally, Billy appears to have also had some enhancements, such as much improved memory recall.