In that era when technology was just beginning, gunpowder had just been applied to war, and mainstream weapons were still bows and arrows and long spears. Giant beasts standing thirty to forty meters tall were a dimensional attack on humanity at the time.
In that era, the humans of this world were on the brink of extinction. The giant beasts destroyed their pre-existing order and economy, causing nations worldwide to collapse. Giant beasts rampaged, and humans began to hide in underground burrows like mice, hoping to survive in this manner.
However, the giant beasts increasingly awakened the ability to sense heat sources and heartbeats, easily discovering humans hiding five meters underground and hunting them down one by one.
Although there were humans who killed giant beasts through traps, catapults, muskets, and spears, these small-scale victories could not conceal the overall defeat of the human defenses.
