Alias

Zookeeper

Nick Name
|
Civilian ID
Dr. Register
Occupation
Research Scientist
Legal Status
Citizen of the United States with a criminal record.
Nation or Planet of Origin
United States
Group Affiliation
None
Base of Operations
San Francisco, California
Height
|
Weight
|
Eye Color
Brown
Hair Color
Brown
Skin Tone
Caucasian - Now Purple
Known Powers
Rare tropical disease and genetic modification enabling the ability to take the form of any animal he can picture in his mind.

Note: Maintaining animals of great mass takes more effort than small animals.

Accessories
|
Common Enemies

Beast Boy

Teen Titans

Regularly Appearing
Teen Titans Vol. 3
First Appearance

Dr. Register

Teen Titans Vol. 3 #13 (Sept. 2004)

Zookeeper

Teen Titans Vol. 3 #14 (Oct. 2004)

Creator
Geoff Johns & Tom Grummett
Origin
In an attempt to cure all diseases Dr. Register sought the biological links between humans and all animals.  He did research at one time with the parents of Garfield Logan and was present when the boy was bitten by a rare Green Monkey - an event which lead to Logan being transformed into Beast Boy.

Acquiring a sample of Sakutia, the rare tropical disease carried by the Green Monkey, Register accidentally infected himself altering his body chemistry and enabling him to transform into any animal he could imagine.  His infection also spread to the children of San Francisco and reversed Logan's ability to transform into animals.  Desperate for a cure Register resolved to dissect Logan - but he was challenged by the Teen Titans.  Defeated, Register was incarcerated in the newly reopened Alcatraz where he waits to strike once again as the Zookeeper.