Ji Lu, Ren Jianmo, Mo Tiangen, and Fan's sister and brother walked into the Hourglass Cube, first registered as a team in front of the artificial intelligence changed into bunny costumes, and then walked through the corridor and entered the foyer.

In the dark, invisible wall and dome hall, stands the huge luminous glass hourglass.

There are countless cube-shaped "sand grains" floating in the air in a gravity-free environment. From a distance, it seems that thousands of fireflies are trapped in a huge transparent insect cage.