Little about the Grey Abbott is known. The Grey Abbott has a large physical frame which has been augumented with cybernetic appendages. Why he has done this is again unknown but what is known is that it was he who created Jean-Paul Valley from a Zygote grew him in a tank filled with animal fluids and tortured him "to impart angelic wrath".
When Azrael went on his quest to learn his origins he found the Grey abbott's lab in the desert and propmtly destroyed it. This caused the Abbott to leave the order. Hearing about a man named Charles who peaked his curiosity to undetake experiments forbidden by the Order, the Grey Abbott had himself commited to Arkham Asylum.
The Grey Abbott's incarceration came to the attention of Brian Bryan, and he persuaded Azrael to break the Abbott out of Arkham. In the incident that followed Charles escaped but was recaptured, the Abbott was shot repeatedly and is presumed dead.
The Grey Abbott has never used weapons but he used to have a laboratory that was advanced well beyond the technology of the rest of the world.
While not possessing any powers beyond those of an ordinary man the grey Abbott's artificial limbs give him a little more stregth than normal. The Grey Abbott has the skills of a genetecist and an unparrelleled knowledge of the human genome.
The Grey Abbott's greatest desire is knowlegde, and will sacrifice anything for it.