1861 The Probable Barriers' Problem

Yes, that was the problem. Sister Orb had the years to work on the formations. That's why she could take control over them. Before the system got an upgrade to its processing power, Sister Orb took over a decade to take control of the Cultivation Suppression Formation. After the system's processing power increased three times, it took only four years to take control over the Continental Barrier Protection Formation to open the tunnel.

However, if each continent in the center of the Realm of Gods was protected by a similar formation, Sister Orb would take years to open a tunnel for each of them. 

Thanks to the twins' newfound wealth, they could totally use the Formation Guild's teleport formations to traverse the continents quickly. A few weeks would be enough as long as the formations were available for use, and it would barely affect their finances. Yet, the Continental Barrier Formations were another story.