Civilization Advancement: Only I Can See the Hidden Rules

Human civilization failed in the "Civilization Advancement Assessment," and civilization perished. Gu Changming was reborn at the last moment before his consciousness faded, returning to before the first assessment began. ... [First Assessment: Day of Silence] [Rule: No sound allowed.] [Duration: 72 hours.] [Punishment for Failure: Death.] Just when everyone was in despair, Gu Changming discovered that he could see something not shown in the assessment... [Hidden Rule: ...]