Swarming silver-gray butterflies danced in the sky.
They weren't real butterflies.
The Ephemeral-type "Legion" drones. Their assigned tasks include battlefield reconnaissance and interference cloaking. As individuals, their performance isn't particularly outstanding, almost negligible in impact. But once combined with a massive number, they form an impenetrable net.
An inescapable surveillance network, which also acts as a jamming net preventing any unauthorized messages from being sent outside.
This net stretches from the ground up to five thousand meters high, covering everything within a 250-kilometer radius under a high-density surveillance network. Any movements are impossible to hide from the eyes and ears of the silver butterflies. At an even higher altitude of twenty thousand meters, massive early warning units overlook the land, coldly observing any movements within a three-thousand-kilometer radius outside the Ephemeral-type alert circle.
