League of Evil
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The League of Evil was a group of evil that Mr. Burns had. The group died from lack of oxygen.
History
Mr. Burns wanted to use them after he was at war with Lisa Simpson and thought he could not lose. When he contacted them, he discovered that they were dead. The died as they did not get any oxygen, being trapped in a room at the power plant for a long time. He ordered Smithers to collect their watches.