Sydney Moist

Dr. Sydney Orville Moist was Jimmy Neutron's favorite heroes who did some research in the Bahama Quadrangle and was secretly reported dead for years until Jimmy and his discovered he was living down underwater in a lair and revealed he made whoever came by the Quadrangle get turned into Algae-Men. But he had an antidote to cure the mutation but Jimmy and his friends successfully escaped.

Weapons
Mutation:  Moist has some food that has mutant algae seeds to turned people into Algae-Man.

Antidote: Moist secretly keeps an antidote to protect him from being mutated.

Abilities
Mutater: Moist doesn't like people trust passing his property so he secretly mutates them into Algae-Men.

Trivia

 * Moist is similar to Captain Nemo from 20,000 Leagues Under the Sea; both are mad scientists who secretly lived in the depths of the ocean in their underwater lab; kidnapping and enslaving anyone who discovers their secret.
 * Sheen heen mentions he was one of the people who would frame Jimmy from stealing the winking George Washington $1 bills in the episode, "Who Framed Jimmy Neutron?".
 * In Jimmy Timmy Power Hour 2: When Nerds Collide!  it is revealed he formed a brief alliance with Professor Calamitous after the two met in a villain convention. However, their alliance was cut off when it was revealed he wasn't keeping an eye out for Jimmy and he was launched into the sky by the CalamiBot.
 * He is not part of  the League of Villains.