The Power of Restriction around the Cyan Yang Secret Realm weakens for a period of one year.
Therefore, the mysterious passage jointly opened by the Nascent Soul True Monarchs would last for one year.
Once the Secret Realm's Power of Restriction begins to strengthen again, the passage will be compressed until it collapses!
Thus, this expedition into the Secret Realm will last for one year.
After one year, the Cultivators inside the Secret Realm must come out. Otherwise, they will have to wait another 480 years for their next chance to leave.
That is, if they can even survive for 480 years inside the Secret Realm!
And that's not even considering how dangerous it is inside.
Four hundred and eighty years is enough time to claim the lives of most Cultivators.
Even for Core Formation Cultivators in their prime, 480 years is long enough to see them to their graves.
