Fortunately, the distance of time and space was a huge limit. There were not many cosmic tunnels in the solar system. Currently, there were only two known planets.
Planet Spirit and Ceres Star.
Actually, before the ancient Heavenly Court was intact, there were quite a lot of them. The transportation hub of the Heavenly Court's small universe, Ceres Star, was connected. It was connected in all directions in the solar system.
As soon as the small universe of the Heavenly Court was sealed, the four small origin universes were sealed. Ceres Star lost its status as a transportation hub.
This made the defense of the solar system less complicated. Unless the three races discovered an undiscovered cosmic tunnel node planet.
However, there were not many planets with cosmic tunnels. For example, in the Milky Way, only one planet out of every hundred planets could have a cosmic tunnel node.
