C376 This thing is called a detonator

By the time Bai Xiaohei returned, the sky was already bright. The few people who had missions of their own had already left, and the soil in the courtyard had already piled up to the height of the academy wall.

In order to prevent the nearby residents from discovering the abnormality of the place, Bai Xiaohei kept all the soil inside his bell, and then took out a large amount of cloth