A powerful enemy who cornered Godzilla
It is vivid to see a marine biologist's face becoming sore and a boy's hands getting sore after touching Hedorah. People who are exposed to the sulfuric acid mist spread by Hedorah turn into skeletons, but rather than such obvious symptoms, the symptoms of people hurting their skin and eyes or collapsing on the spot are more realistic and scary. The depiction of metals being ruined and rusted by sulfuric acid is also disgusting.
Another characteristic of Hedorah is that it grows and becomes gigantic. He evolves in stages such as underwater stage, landing stage, flight stage, and complete stage, gaining new abilities each time and overwhelming Godzilla, but the way he grows through stages is reminiscent of the " Shin Godzilla " version of Godzilla. I also let them do it. Speaking of Godzilla, he is forced to struggle against Hedorah, whose power is increasing. The area where the sludge ball hits him burns, and even though he is the King of Monsters in close combat, his throat hurts and his neck gets scratched. In the end, his right arm is melted and turned into a skeleton, and his left eye is burnt out, but even in this form, he still faces Hedorah with a frightening look on his face. Their anger at having their territory, the ocean (or the earth) polluted, is tremendous.
However, it was humanity that gave birth to Hedorah. Originally, mineral life forms that came from space with meteorites coalesced with the sludge that accumulated in the ocean and became monsters, but it was humans who made them so strong. In other words, it was humanity who indirectly pushed Godzilla into such a corner, and the one who roared and glared at him with a sore face may have been Hedorah as well as humanity on the other side.
It's strange, but it's a fear similar to the original Godzilla.