True to his name, The Alchemist is a chemical genius carrot with robotic arms. Despite the fact that he is a villain, his level of intimidation is rather low due to the fact that he still lives with his mother who calls him "Cubby" and has pig-snorting laugh. He and his mother only appeared in Leggo My Ego!
- The Alchemist makes excellent coffee.
- Rumor has it that The Alchemist went evil when he tried to win a science contest and made a project too evil to allow himself to win. He then sulked by himself thinking that he lost the trophy that was rightfully his and went more bad than he ever was...
- He has a squirting flower, and is voiced by Jerry Nelson.