Thomas Edison was certainly a "Hero of Science"--he invented the lightbulb! He was also a high-ranking Ekaterina and an avid Clue hunter. When he hired another Ekat, Nikola Tesla, to work with him, their branch leadership was sure it was only a matter of time before they found all 39 Clues. Edison and Tesla had a terrible argument and became bitter rivals. No one is exactly sure what caused the fight--or whether they had already completed their secret project. Collect all cards in this combination to unlock a Clue!