Godzilla vs Hedorah: Godzilla vs the Smog Monster

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 Hedora 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 who doesn't need to sing protest songs or try to enact new laws to get things done. Nobody and nothing can stop Godzilla when he decides to push an environmental issue, and while Hedorah may be the dirtiest opponent Godzilla has ever faced, his name is going to be mud by the time he's been stomped into the whole Earth a few dozen times.