Goofs

When they're crawling through the lowering ceiling, the supposed oil lamp is dragged horizontally, which would have caused the oil to spill and ignite. The lamp is then used to stop the ceiling and as it's crushed, it's obvious that it's an electric light.

Inside the underground palace are many glass jars supposedly over 2000 years old. Many sources date the first manufacture of glass to the 5th century AD. However, the earliest archaeological evidence for glass manufacture in China comes from the Warring States period (475 BC to 221 BC).

When the stone block is being lowered, they place a lamp on a raised rock, which would have stopped the rock from lowering.