Beneath the pit, there was a space that was reminiscent of a warehouse. Inside that space, Han Sen saw many giant metal cubes sitting in lines. They looked like storage containers, but they were bigger than the sort of boxes you'd expect to find in a warehouse.
When Han Sen got closer, he realized that each cube was covered in giant handprints. He had seen one of these metallic cubes before in Narrow-Moon; the blue metal cube the Rebate had retrieved from the Ligu Ruins looked just like the boxes he was seeing now.
When that blue metallic cube was opened, it released a collection of blue gold demon bugs. They assaulted Narrow-Moon, dealing great damage to the system. And while that was bad, Han Sen had managed to obtain his Demon Bug Bai Sema through the ordeal, which had saved his life numerous times already.
That entire scenario, and the subsequent results, were an affair Han Sen would never forget.