Dr. Gangreen is a fictional character known for his role as a villain in various media, particularly in the realm of horror and science fiction. He is often depicted as a mad scientist with a penchant for creating grotesque experiments and monstrous creatures. His character typically embodies themes of obsession and the consequences of unethical scientific practices. The character has appeared in different formats, including comic books and television shows. Dr. Gangreen is often associated with the Toxic Crusaders, a group of heroes fighting against pollution and environmental destruction. His exaggerated personality and sinister plans make him a memorable antagonist in the stories he inhabits.