The Vortex’s Discovery

At a spot 287 meters under Golden Tooth's headquarters was an underground lab sealed entirely shut by super alloy that was several meters thick. It completely blocked off all tremors and noise from the outside world. 

When the lair on the surface sank into a chaotic battle full of explosions and fire, this place remained dark and quiet. The air was so thick that it was nearly suffocating, and it was like a grave that had been sealed for a thousand years. 

At that moment, the quiet in the grave was broken by a strange dripping sound. 

Drip. Drip. Drip. Drip. Drip. 

The sound came from the ventilation vent. 

The underground lab had two different air circulation systems. 

One system was similar to the ones used in orbital space stations. It could perfectly recycle oxygen and carbon dioxide within the room, so there was no need for contact with the outside world.