Two walls

As soon as everyone entered the next challenge room, the door closed.

Suddenly, on a stone pillar, a magic circle appeared, emitting a dazzling light.

If Lathel were here, he would definitely recognise that as the stone pillar he chose to enter the trial space.

A stream of white smoke shaped like an Eastern dragon flew out of that magic circle.

The dragon was more than a hundred metres long. Although it is condensed from smoke, its eyes were formed from two lightning balls carrying extremely destructive power.

The smoke dragon suddenly disintegrated, then condensed into the image of a young man. However, because this young man was also condensed from smoke, his face could not be seen clearly.

He waved his hand, and an hourglass appeared in mid-air. Suddenly, a black vortex appeared in the space in front of that young man.

From inside that vortex, a puppet nearly two metres tall stepped out; yes, that was the Demon Lord's puppet.