In the Noah continent, where garen was born, this kind of small main material world, as long as one flew in a straight line towards the sky, after flying tens of thousands of meters high, they would come into contact with the invisible and intangible but real plane barrier.
The crystal wall of the plane separated the countless prime material worlds.
It was both protection and restraint.
Basically, only high-level spellcasters and above had the ability to travel between planes.
If one was not a spellcaster, but a warrior or other profession, one would even need to reach the legendary level to travel between dimensions.
It was different from the main material world.
The Prime Material Plane, where the alpha Empire was located, was as vast as a Galaxy.
