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Forget about acid rain and global warming! The worst ecological nightmare is actually Hedorah, which starts off small but quickly mutates into a giant flying monster capable of wiping out all life on whatever unfortunate planet it lands on! And since Hedorah grows by consuming the toxic gases and chemicals mankind has spilled into the air and water, in the early 1970s that means that its potential growth is unlimited! Fortunately for the human race, the Earth has an ultimate green defender.