Doctor Vile
Dr. Vile is a mad scientist from The Little Mermaid series who tried to capture Sebastian and use him for his sinister crab experiments until Sebastian started bonding with his young good-hearted apprentice, Daniel in the episode; "Island of Fear." His electric waterwheel was responsible for polluting the ocean which caused everyone to fall sick until Ariel found a way to destroy it by throwing a monkey wrench at it.
In Ultima, Ursula the Sea Witch met up with Dr. Vile and told him about the concept of other worlds, the Organization, and of the darkness itself. Sensing this as an oppurtunity to continue his mad experiments, Vile accepted Ursula's request for him to join the Organization, and is currently working as a member of the Org Tech Division's bioengineering sector.