Jiang Bai's shadow control powers became evident early in his life. The Crimson Spider Lin Kuei found out about this, slew his parents, and adopted him into their clan. His powers worked well with his assassin training allowing Shadowspinner to be one of the most feared assassins in the world.

On a mission to assassinate a wealthy industrialist, Shadowspinner found himself in the middle of a golf course on a cloudy day. With no other source of shadow, he attempted to form a shadow assassin out of his own shadow.

But being so closely connected with the shadow, Bai found himself splitting in twain. He wrestled to merge the duplicates of himself back together, but to no avail. One of the pair was more sinister than the original Bai, the other less so. In an effort to preserve its integrity the 'better' Bai opened up a door to the shadow dimension and fled. The 'more evil' Bai found that it had lost the power to enter the shadow dimension and, thus, could not pursue his twin.

This Bai wavered between doing things for himself and doing things to help others. When the Immortals were re-formed, he joined as Dog mostly so that he can grab more of the spotlight. The other Bai remained a part of the Crimson Spider.

Bai has become Dog for one reason: to show the world just how good he is at what he does. Once one of the most feared assassins in the world, he has developed a conscience - a small one to be sure, but a conscience nonetheless. He is no longer a cold-blooded killer, but he still has problems caring for anyone but himself. He will take opportunities to make sure that the camera and spotlight are on him.

"You want to see something cool, watch me."

Dog is an expert at An Ch'i and Lin Kuei. He is a bit more cerebral than Bai Shadowspinner having even taken the time to learn the science of his dimension control powers.

Dog wears the standard Immortals red uniform, over which he wears a heavy black coat.