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The Once-ler, the main antagonist of The Lorax, was voiced by Ed Helms. The Once-ler is a greedy businessman who chops down the Truffula trees to make Thneeds, a popular clothing item. His actions lead to the destruction of the environment and the departure of the Lorax, a creature who speaks for the trees. Helms' voice performance captures the Once-ler's charm and charisma, as well as his selfishness and arrogance.