Mysterious Beings

Mysterious Beings is a term used to refer to sentient creatures that terrorize the cities of Japan and pose a threat to society. They have been appearing more frequently in the past 15 years, but humanity still is unaware how such creatures came into existence. It is still unknown what their actual purpose is, but it seems that all these creatures are hostile towards mankind, wreck havoc in the cities and terrorize its citizens. However some Mysterious Beings seem to have been normal beings or individuals which through certain means gained superpowers or mutations via scientific or supernatural means while others appear to be sentient races that have been dormant or living in seclusion from the surface world. Mysterious Beings are especially concentrated in Z-City and Q-City. These beings are the reason the Heroes Association was founded by Chinner.

Disaster Levels
The attacks by Mysterious Beings have a scale on how destructive the attack is, which goes from Wolf level to God level.