They appear mainly because of a farmer named Thomas Gelsi.

He lived in Michelle, South Dakota, USA. At that time, his corn had been eaten clean by locusts. The local government not only failed to make up for this, but also decided to hold a corn exhibition.

This made Gelsi very angry, so he used his skillful hands to make many iron locusts, and the tickets of these iron locusts helped Gelsi to temporarily solve the current life crisis.

Gelsi was very happy about this. He began to try to make other insects, such as spiders and fleas. And after he got angry, others began to stir.

For example, those weapons shops started selling shotguns by using postcards from Wisconsin about giant locusts. However, after the US authorities intervened in this matter, the truth was quickly revealed.

At that time, a Wisconsin newspaper called the Daily Tribune interviewed the producers of postcards, and according to them, these postcards were just a little joke, and they hoped it would make people have some fun.