The Arachnid is an alien species of green spider-like bugs that invades the Special Region when one of the dimension rift opens to their homeword. They are proved to be far more dangerous than the JSDF due to their zerg-like vast number, hyper-evolution, aggressiveness and tough skin that prove too much for modern firearms as well as Demi-Goddess with superhuman power like Rory Mercury to even handle them.
They manage to nearly slaughter all JSDF personnel and Special Region citizen to the point that even the support of Rory Mercury is pale in comparison to vast number of the bugs as she is nearly being overwhelmed by them. Consequently, Lelei forces to close the gate with her magic to prevent further calamity.
Warrior Bugs: the basic soldiers in the Arachnid army, these green spider-like creatures often attack their enemies in mass swarm attack to overwhelm the enemy positions. They are quite tough due to their natural exo-skeleton and extremely aggressive since it takes more than half a magazine of a assault rifle to kill one and their number is vast enough to pin down a superhuman Demi-goddess like Rory with little difficulty.
Flying Bugs: the flying bugs act as air supports for the Arachnid army. They are weaker than warrior bugs since Itami can kill one with a well-placed shot from his saw-off shotgun, but they are strong enough to decapitate a man with their wings.
Shield Bugs: shield bugs act as armored troops of the Arachnids in which their exoskeletons are durable enough to endure dozens of 50 cal shots and it takes three grenades as well as a blast from a tank to put them down.
Mantis Bugs: Mantis Bugs are shock troopers of the Arachnid horde. They are equipped with heavy exoskeleton armors and sharp claws strong enough to cut a Humvee in half.
Tentacles: this creature is unknown since it is only shown when it kills Liu by pulling him inside the Arachnid homeworld through the dimensional rift.
- The Arachnid is the only species so far that poses real and serious threat to the JSDF and Apostle, especially since Rory Mercury has tremendous difficulty fighting them.
- So far, only the JSDF, Alnus mercenaries and Apostles like Rory and Giselle face them in battle.