These 6 monsters were actually a scout team among the monster swarm.
The entire horde consisted of 3533 monsters, all controlled by the commander of Skuru's expeditionary force—Langqi.
He had no choice but to control them.
Monsters had low intelligence. Without deliberate control, they would become disoriented. Not only would they be unable to methodically destroy Japan, they might even start attacking each other!
Because of this, when the Skuru people created them, they implanted control chips into the brains of each monster, allowing Langqi to command them.
After the Monster swarm emerged from the "Gravity Funnel," Langqi ordered most of the monsters to destroy Japan's Kyoto Prefecture, while simultaneously sending out three squads of twelve flying monsters, not for destruction, but specifically to scout out human society.
The first squad of three flew northward all the way along Hokkaido and Sakhalin Island into the Asian continent;
