Just as Cho'Gath was grinding Korea into the dirt.
The situation in Tianxiong Underground City, Antarctica, was also deteriorating rapidly.
More and more Burrowing Earth Dragons passed through the wormhole onto Blue Star, tunneling toward Tianxiong City from every direction.
The red dots packed onto the Seismic Wave Monitoring System were already impossible to count. There were over a hundred of them!
Tianxiong City's unmanned underground military factory was running at full capacity.
Robotic assembly lines produced Cubic Nitrogen Explosive and C4 around the clock, while Combat Robots carried them to positions along the outer walls and planted them in advance.
A Burrowing Earth Dragon gnawed through a wall, an explosion rang out, the tunnel collapsed, and the dragon's corpse blocked the passage.
If it had only been Burrowing Earth Dragons, Tianxiong City could have held out.
But the Demon Clan had more than just Burrowing Earth Dragons.
At some point, the AI monitoring system had begun issuing new alerts nonstop, detecting unauthorized biological activity in multiple sectors inside the city.
Among them were quite a few fifth-order and sixth-rank members of the Demon Clan!
These demons did not take the same routes as the Burrowing Earth Dragons. Instead, they entered through the main tunnel connecting Tianxiong City to the surface, the ventilation ducts, and the drainage pipes that the Burrowing Earth Dragons had opened up.
Like rats, they squeezed into the city through every available opening.
The alloy grilles in the ventilation ducts had a hardness of HRC 60, but against the claws of fifth-order demons, they were no different from aluminum foil.
With a few tearing motions, an entire grille was twisted into a corkscrew and tossed aside, and a dark figure flipped out of the duct opening and dropped into the city.
The sixth-rank demons were even